diff --git a/changes/2942.misc.rst b/changes/2942.misc.rst
new file mode 100644
index 0000000000..41bb0166c3
--- /dev/null
+++ b/changes/2942.misc.rst
@@ -0,0 +1 @@
+The initialization process for widgets has been internally restructured to avoid unnecessary style reapplications.
diff --git a/changes/2942.removal.rst b/changes/2942.removal.rst
new file mode 100644
index 0000000000..365ef380c1
--- /dev/null
+++ b/changes/2942.removal.rst
@@ -0,0 +1 @@
+Widgets now create and return their implementations via a ``_create()`` method. A user-created custom widget that inherits from an existing Toga widget and uses its same implementation will require no changes; any user-created widgets that need to specify their own implementation should do so in ``_create()`` and return it. Existing user code inheriting from Widget that assigns its implementation before calling ``super().__init__()`` will continue to function, but give a RuntimeWarning; unfortunately, this change breaks any existing code that doesn't create its implementation until afterward. Such usage will now raise an exception.
diff --git a/cocoa/src/toga_cocoa/widgets/base.py b/cocoa/src/toga_cocoa/widgets/base.py
index 28da6271fb..06e6264135 100644
--- a/cocoa/src/toga_cocoa/widgets/base.py
+++ b/cocoa/src/toga_cocoa/widgets/base.py
@@ -9,12 +9,10 @@ class Widget:
     def __init__(self, interface):
         super().__init__()
         self.interface = interface
-        self.interface._impl = self
         self._container = None
         self.constraints = None
         self.native = None
         self.create()
-        self.interface.style.reapply()
 
     @abstractmethod
     def create(self): ...
diff --git a/cocoa/src/toga_cocoa/widgets/button.py b/cocoa/src/toga_cocoa/widgets/button.py
index 1ef61bcefd..eadb8e2b92 100644
--- a/cocoa/src/toga_cocoa/widgets/button.py
+++ b/cocoa/src/toga_cocoa/widgets/button.py
@@ -32,7 +32,6 @@ def create(self):
         self._icon = None
 
         self.native.buttonType = NSMomentaryPushInButton
-        self._set_button_style()
 
         self.native.target = self.native
         self.native.action = SEL("onPress:")
diff --git a/core/src/toga/style/applicator.py b/core/src/toga/style/applicator.py
index 2b0c17ee75..43674a0d24 100644
--- a/core/src/toga/style/applicator.py
+++ b/core/src/toga/style/applicator.py
@@ -1,16 +1,34 @@
 from __future__ import annotations
 
+import warnings
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
     from toga.widgets.base import Widget
 
+# Make sure deprecation warnings are shown by default
+warnings.filterwarnings("default", category=DeprecationWarning)
+
 
 class TogaApplicator:
     """Apply styles to a Toga widget."""
 
-    def __init__(self, widget: Widget):
-        self.widget = widget
+    def __init__(self, widget: None = None):
+        if widget is not None:
+            warnings.warn(
+                "Widget parameter is deprecated. Applicator will be given a reference "
+                "to its widget when it is assigned as that widget's applicator.",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+
+    @property
+    def widget(self) -> Widget:
+        """The widget to which this applicator is assigned.
+
+        Syntactic sugar over the node attribute set by Travertino.
+        """
+        return self.node
 
     def refresh(self) -> None:
         # print("RE-EVALUATE LAYOUT", self.widget)
diff --git a/core/src/toga/widgets/activityindicator.py b/core/src/toga/widgets/activityindicator.py
index 102f44d129..4ac5c2ab18 100644
--- a/core/src/toga/widgets/activityindicator.py
+++ b/core/src/toga/widgets/activityindicator.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Literal
+from typing import Any, Literal
 
 from .base import StyleT, Widget
 
@@ -22,11 +22,12 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        self._impl = self.factory.ActivityIndicator(interface=self)
-
         if running:
             self.start()
 
+    def _create(self) -> Any:
+        return self.factory.ActivityIndicator(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/base.py b/core/src/toga/widgets/base.py
index 61d135cb9f..0d179ac8ac 100644
--- a/core/src/toga/widgets/base.py
+++ b/core/src/toga/widgets/base.py
@@ -2,6 +2,7 @@
 
 from builtins import id as identifier
 from typing import TYPE_CHECKING, Any, TypeVar
+from warnings import warn
 
 from travertino.declaration import BaseStyle
 from travertino.node import Node
@@ -33,18 +34,70 @@ def __init__(
         :param style: A style object. If no style is provided, a default style
             will be applied to the widget.
         """
-        super().__init__(
-            style=style if style else Pack(),
-            applicator=TogaApplicator(self),
-        )
+        super().__init__(style=style if style is not None else Pack())
 
         self._id = str(id if id else identifier(self))
         self._window: Window | None = None
         self._app: App | None = None
-        self._impl: Any = None
 
+        # Get factory and assign implementation
         self.factory = get_platform_factory()
 
+        ###########################################
+        # Backwards compatibility for Toga <= 0.4.8
+        ###########################################
+
+        # Just in case we're working with a third-party widget created before
+        # the _create() mechanism was added, which has already defined its
+        # implementation. We still want to call _create(), to issue the warning and
+        # inform users about where they should be creating the implementation, but if
+        # there already is one, we don't want to do the assignment and thus replace it
+        # with None.
+
+        impl = self._create()
+
+        if not hasattr(self, "_impl"):
+            self._impl = impl
+
+        #############################
+        # End backwards compatibility
+        #############################
+
+        self.applicator = TogaApplicator()
+
+        ##############################################
+        # Backwards compatibility for Travertino 0.3.0
+        ##############################################
+
+        # The below if block will execute when using Travertino 0.3.0. For future
+        # versions of Travertino, these assignments (and the reapply) will already have
+        # been handled "automatically" by assigning the applicator above; in that case,
+        # we want to avoid doing a second, redundant style reapplication.
+
+        # This whole section can be removed as soon as there's a newer version of
+        # Travertino to set as Toga's minimum requirement.
+
+        if not hasattr(self.applicator, "node"):  # pragma: no cover
+            self.applicator.node = self
+            self.style._applicator = self.applicator
+            self.style.reapply()
+
+        #############################
+        # End backwards compatibility
+        #############################
+
+    def _create(self) -> Any:
+        """Create a platform-specific implementation of this widget.
+
+        A subclass of Widget should redefine this method to return its implementation.
+        """
+        warn(
+            "Widgets should create and return their implementation in ._create(). This "
+            "will be an exception in a future version.",
+            RuntimeWarning,
+            stacklevel=2,
+        )
+
     def __repr__(self) -> str:
         return f"<{self.__class__.__name__}:0x{identifier(self):x}>"
 
diff --git a/core/src/toga/widgets/box.py b/core/src/toga/widgets/box.py
index 5f84160fb1..48ab114c78 100644
--- a/core/src/toga/widgets/box.py
+++ b/core/src/toga/widgets/box.py
@@ -24,14 +24,14 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a Box
-        self._impl = self.factory.Box(interface=self)
-
         # Children need to be added *after* the impl has been created.
         self._children: list[Widget] = []
         if children is not None:
             self.add(*children)
 
+    def _create(self):
+        return self.factory.Box(interface=self)
+
     @property
     def enabled(self) -> bool:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/button.py b/core/src/toga/widgets/button.py
index f8c2471d9c..0c07a76d15 100644
--- a/core/src/toga/widgets/button.py
+++ b/core/src/toga/widgets/button.py
@@ -44,9 +44,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a Button
-        self._impl = self.factory.Button(interface=self)
-
         # Set a dummy handler before installing the actual on_press, because we do not
         # want on_press triggered by the initial value being set
         self.on_press = None
@@ -63,6 +60,9 @@ def __init__(
         self.on_press = on_press
         self.enabled = enabled
 
+    def _create(self) -> Any:
+        return self.factory.Button(interface=self)
+
     @property
     def text(self) -> str:
         """The text displayed on the button.
diff --git a/core/src/toga/widgets/canvas.py b/core/src/toga/widgets/canvas.py
index 0941a5d8ce..355b400144 100644
--- a/core/src/toga/widgets/canvas.py
+++ b/core/src/toga/widgets/canvas.py
@@ -1239,14 +1239,10 @@ def __init__(
         :param on_alt_release: Initial :any:`on_alt_release` handler.
         :param on_alt_drag: Initial :any:`on_alt_drag` handler.
         """
-
         super().__init__(id=id, style=style)
 
         self._context = Context(canvas=self)
 
-        # Create a platform specific implementation of Canvas
-        self._impl = self.factory.Canvas(interface=self)
-
         # Set all the properties
         self.on_resize = on_resize
         self.on_press = on_press
@@ -1257,6 +1253,9 @@ def __init__(
         self.on_alt_release = on_alt_release
         self.on_alt_drag = on_alt_drag
 
+    def _create(self) -> Any:
+        return self.factory.Canvas(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/dateinput.py b/core/src/toga/widgets/dateinput.py
index 7408f38ae2..b277023bf8 100644
--- a/core/src/toga/widgets/dateinput.py
+++ b/core/src/toga/widgets/dateinput.py
@@ -51,9 +51,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a DateInput
-        self._impl = self.factory.DateInput(interface=self)
-
         self.on_change = None
         self.min = min
         self.max = max
@@ -61,6 +58,9 @@ def __init__(
         self.value = value
         self.on_change = on_change
 
+    def _create(self) -> Any:
+        return self.factory.DateInput(interface=self)
+
     @property
     def value(self) -> datetime.date:
         """The currently selected date. A value of ``None`` will be converted into
diff --git a/core/src/toga/widgets/detailedlist.py b/core/src/toga/widgets/detailedlist.py
index a14f698d31..434c08eab5 100644
--- a/core/src/toga/widgets/detailedlist.py
+++ b/core/src/toga/widgets/detailedlist.py
@@ -85,6 +85,16 @@ def __init__(
         :param on_refresh: Initial :any:`on_refresh` handler.
         :param on_delete: **DEPRECATED**; use ``on_primary_action``.
         """
+        # Prime the attributes and handlers that need to exist when the widget is
+        # created.
+        self._accessors = accessors
+        self._missing_value = missing_value
+        self._primary_action = primary_action
+        self._secondary_action = secondary_action
+        self.on_select = None
+
+        self._data: SourceT | ListSource = None
+
         super().__init__(id=id, style=style)
 
         ######################################################################
@@ -104,24 +114,15 @@ def __init__(
         # End backwards compatibility.
         ######################################################################
 
-        # Prime the attributes and handlers that need to exist when the
-        # widget is created.
-        self._accessors = accessors
-        self._missing_value = missing_value
-        self._primary_action = primary_action
-        self._secondary_action = secondary_action
-        self.on_select = None
-
-        self._data: SourceT | ListSource = None
-
-        self._impl = self.factory.DetailedList(interface=self)
-
         self.data = data
         self.on_primary_action = on_primary_action
         self.on_secondary_action = on_secondary_action
         self.on_refresh = on_refresh
         self.on_select = on_select
 
+    def _create(self) -> Any:
+        return self.factory.DetailedList(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/divider.py b/core/src/toga/widgets/divider.py
index 4b7edf62c1..8a7db69fe1 100644
--- a/core/src/toga/widgets/divider.py
+++ b/core/src/toga/widgets/divider.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Literal
+from typing import Any, Literal
 
 from toga.constants import Direction
 
@@ -29,10 +29,11 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a Divider
-        self._impl = self.factory.Divider(interface=self)
         self.direction = direction
 
+    def _create(self) -> Any:
+        return self.factory.Divider(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/imageview.py b/core/src/toga/widgets/imageview.py
index 663b3d1071..7011e059ab 100644
--- a/core/src/toga/widgets/imageview.py
+++ b/core/src/toga/widgets/imageview.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Literal
+from typing import TYPE_CHECKING, Any, Literal
 
 from travertino.size import at_least
 
@@ -83,12 +83,16 @@ def __init__(
         :param style: A style object. If no style is provided, a default style will be
             applied to the widget.
         """
-        super().__init__(id=id, style=style)
         # Prime the image attribute
         self._image = None
-        self._impl = self.factory.ImageView(interface=self)
+
+        super().__init__(id=id, style=style)
+
         self.image = image
 
+    def _create(self) -> Any:
+        return self.factory.ImageView(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/label.py b/core/src/toga/widgets/label.py
index 83fb1ba7a6..b448ae5905 100644
--- a/core/src/toga/widgets/label.py
+++ b/core/src/toga/widgets/label.py
@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+from typing import Any
+
 from .base import StyleT, Widget
 
 
@@ -19,11 +21,11 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a Label
-        self._impl = self.factory.Label(interface=self)
-
         self.text = text
 
+    def _create(self) -> Any:
+        return self.factory.Label(interface=self)
+
     def focus(self) -> None:
         """No-op; Label cannot accept input focus."""
         pass
diff --git a/core/src/toga/widgets/mapview.py b/core/src/toga/widgets/mapview.py
index dd69651b07..425a5a65ab 100644
--- a/core/src/toga/widgets/mapview.py
+++ b/core/src/toga/widgets/mapview.py
@@ -155,8 +155,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        self._impl: Any = self.factory.MapView(interface=self)
-
         self._pins = MapPinSet(self, pins)
 
         if location:
@@ -169,6 +167,9 @@ def __init__(
 
         self.on_select = on_select
 
+    def _create(self) -> Any:
+        return self.factory.MapView(interface=self)
+
     @property
     def location(self) -> toga.LatLng:
         """The latitude/longitude where the map is centered.
diff --git a/core/src/toga/widgets/multilinetextinput.py b/core/src/toga/widgets/multilinetextinput.py
index afbc10a2b5..c966ad036b 100644
--- a/core/src/toga/widgets/multilinetextinput.py
+++ b/core/src/toga/widgets/multilinetextinput.py
@@ -39,12 +39,8 @@ def __init__(
         :param on_change: A handler that will be invoked when the value of
             the widget changes.
         """
-
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a MultilineTextInput
-        self._impl = self.factory.MultilineTextInput(interface=self)
-
         # Set a dummy handler before installing the actual on_change, because we do not
         # want on_change triggered by the initial value being set
         self.on_change = None
@@ -55,6 +51,9 @@ def __init__(
         self.placeholder = placeholder
         self.on_change = on_change
 
+    def _create(self) -> Any:
+        return self.factory.MultilineTextInput(interface=self)
+
     @property
     def placeholder(self) -> str:
         """The placeholder text for the widget.
diff --git a/core/src/toga/widgets/numberinput.py b/core/src/toga/widgets/numberinput.py
index 8a9907fe67..d05edf937f 100644
--- a/core/src/toga/widgets/numberinput.py
+++ b/core/src/toga/widgets/numberinput.py
@@ -147,7 +147,6 @@ def __init__(
         self._max: Decimal | None = None
 
         self.on_change = None
-        self._impl = self.factory.NumberInput(interface=self)
 
         self.readonly = readonly
         self.step = step
@@ -157,6 +156,9 @@ def __init__(
 
         self.on_change = on_change
 
+    def _create(self) -> Any:
+        return self.factory.NumberInput(interface=self)
+
     @property
     def readonly(self) -> bool:
         """Can the value of the widget be modified by the user?
diff --git a/core/src/toga/widgets/optioncontainer.py b/core/src/toga/widgets/optioncontainer.py
index a1a6c1fc26..8a90f64d36 100644
--- a/core/src/toga/widgets/optioncontainer.py
+++ b/core/src/toga/widgets/optioncontainer.py
@@ -397,8 +397,6 @@ def __init__(
         self._content = OptionList(self)
         self.on_select = None
 
-        self._impl = self.factory.OptionContainer(interface=self)
-
         if content is not None:
             for item in content:
                 if isinstance(item, OptionItem):
@@ -424,6 +422,9 @@ def __init__(
 
         self.on_select = on_select
 
+    def _create(self) -> Any:
+        return self.factory.OptionContainer(interface=self)
+
     @property
     def enabled(self) -> bool:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/passwordinput.py b/core/src/toga/widgets/passwordinput.py
index 48548b4935..b72bcba0f0 100644
--- a/core/src/toga/widgets/passwordinput.py
+++ b/core/src/toga/widgets/passwordinput.py
@@ -1,10 +1,12 @@
 from __future__ import annotations
 
+from typing import Any
+
 from .textinput import TextInput
 
 
 class PasswordInput(TextInput):
     """Create a new password input widget."""
 
-    def _create(self) -> None:
-        self._impl = self.factory.PasswordInput(interface=self)
+    def _create(self) -> Any:
+        return self.factory.PasswordInput(interface=self)
diff --git a/core/src/toga/widgets/progressbar.py b/core/src/toga/widgets/progressbar.py
index 49f2e67575..0d8e1cebcb 100644
--- a/core/src/toga/widgets/progressbar.py
+++ b/core/src/toga/widgets/progressbar.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Literal, SupportsFloat
+from typing import Any, Literal, SupportsFloat
 
 from .base import StyleT, Widget
 
@@ -32,14 +32,15 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        self._impl = self.factory.ProgressBar(interface=self)
-
         self.max = max
         self.value = value
 
         if running:
             self.start()
 
+    def _create(self) -> Any:
+        return self.factory.ProgressBar(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/scrollcontainer.py b/core/src/toga/widgets/scrollcontainer.py
index 92c7e61722..a69e9d2673 100644
--- a/core/src/toga/widgets/scrollcontainer.py
+++ b/core/src/toga/widgets/scrollcontainer.py
@@ -45,15 +45,15 @@ def __init__(
         self._content: Widget | None = None
         self.on_scroll = None
 
-        # Create a platform specific implementation of a Scroll Container
-        self._impl = self.factory.ScrollContainer(interface=self)
-
         # Set all attributes
         self.vertical = vertical
         self.horizontal = horizontal
         self.content = content
         self.on_scroll = on_scroll
 
+    def _create(self) -> Any:
+        return self.factory.ScrollContainer(interface=self)
+
     @Widget.app.setter
     def app(self, app) -> None:
         # Invoke the superclass property setter
diff --git a/core/src/toga/widgets/selection.py b/core/src/toga/widgets/selection.py
index 2425c3e716..667877d35b 100644
--- a/core/src/toga/widgets/selection.py
+++ b/core/src/toga/widgets/selection.py
@@ -69,7 +69,6 @@ def __init__(
         self._items: SourceT | ListSource
 
         self.on_change = None  # needed for _impl initialization
-        self._impl = self.factory.Selection(interface=self)
 
         self._accessor = accessor
         self.items = items
@@ -79,6 +78,9 @@ def __init__(
         self.on_change = on_change
         self.enabled = enabled
 
+    def _create(self) -> Any:
+        return self.factory.Selection(interface=self)
+
     @property
     def items(self) -> SourceT | ListSource:
         """The items to display in the selection.
diff --git a/core/src/toga/widgets/slider.py b/core/src/toga/widgets/slider.py
index b71f73e2cb..2ebd29fa00 100644
--- a/core/src/toga/widgets/slider.py
+++ b/core/src/toga/widgets/slider.py
@@ -39,6 +39,8 @@ def __call__(self, widget: Slider, /, **kwargs: Any) -> object:
 
 
 class Slider(Widget):
+    _MIN_WIDTH = 100
+
     def __init__(
         self,
         id: str | None = None,
@@ -72,7 +74,6 @@ def __init__(
             :any:`range` of the slider. Defaults to ``(0, 1)``.
         """
         super().__init__(id=id, style=style)
-        self._impl = self.factory.Slider(interface=self)
 
         ######################################################################
         # 2023-06: Backwards compatibility
@@ -115,7 +116,8 @@ def __init__(
 
         self.enabled = enabled
 
-    _MIN_WIDTH = 100
+    def _create(self) -> Any:
+        return self.factory.Slider(interface=self)
 
     # Backends are inconsistent about when they produce events for programmatic changes,
     # so we deal with those in the interface layer.
diff --git a/core/src/toga/widgets/splitcontainer.py b/core/src/toga/widgets/splitcontainer.py
index 5d76f2a24a..29493e856e 100644
--- a/core/src/toga/widgets/splitcontainer.py
+++ b/core/src/toga/widgets/splitcontainer.py
@@ -2,7 +2,7 @@
 
 import sys
 from collections.abc import Sequence
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Any
 
 from toga.app import App
 from toga.constants import Direction
@@ -45,13 +45,13 @@ def __init__(
         super().__init__(id=id, style=style)
         self._content: list[SplitContainerContentT] = [None, None]
 
-        # Create a platform specific implementation of a SplitContainer
-        self._impl = self.factory.SplitContainer(interface=self)
-
         if content:
             self.content = content
         self.direction = direction
 
+    def _create(self) -> Any:
+        return self.factory.SplitContainer(interface=self)
+
     @property
     def enabled(self) -> bool:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/switch.py b/core/src/toga/widgets/switch.py
index 1fd202301f..927e45a8d1 100644
--- a/core/src/toga/widgets/switch.py
+++ b/core/src/toga/widgets/switch.py
@@ -41,8 +41,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        self._impl = self.factory.Switch(interface=self)
-
         self.text = text
 
         # Set a dummy handler before installing the actual on_change, because we do not
@@ -54,6 +52,9 @@ def __init__(
 
         self.enabled = enabled
 
+    def _create(self) -> Any:
+        return self.factory.Switch(interface=self)
+
     @property
     def text(self) -> str:
         """The text label for the Switch.
diff --git a/core/src/toga/widgets/table.py b/core/src/toga/widgets/table.py
index d0e991e0fb..f450c77d4d 100644
--- a/core/src/toga/widgets/table.py
+++ b/core/src/toga/widgets/table.py
@@ -78,8 +78,6 @@ def __init__(
             defined.
         :param on_double_click: **DEPRECATED**; use :attr:`on_activate`.
         """
-        super().__init__(id=id, style=style)
-
         ######################################################################
         # 2023-06: Backwards compatibility
         ######################################################################
@@ -119,12 +117,16 @@ def __init__(
         self.on_activate = None
         self._data = None
 
-        self._impl = self.factory.Table(interface=self)
+        super().__init__(id=id, style=style)
+
         self.data = data
 
         self.on_select = on_select
         self.on_activate = on_activate
 
+    def _create(self) -> Any:
+        return self.factory.Table(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/textinput.py b/core/src/toga/widgets/textinput.py
index cea1d1e44a..20b62f075d 100644
--- a/core/src/toga/widgets/textinput.py
+++ b/core/src/toga/widgets/textinput.py
@@ -81,9 +81,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of the widget
-        self._create()
-
         self.placeholder = placeholder
         self.readonly = readonly
 
@@ -103,8 +100,8 @@ def __init__(
         self.on_lose_focus = on_lose_focus
         self.on_gain_focus = on_gain_focus
 
-    def _create(self) -> None:
-        self._impl = self.factory.TextInput(interface=self)
+    def _create(self) -> Any:
+        return self.factory.TextInput(interface=self)
 
     @property
     def readonly(self) -> bool:
diff --git a/core/src/toga/widgets/timeinput.py b/core/src/toga/widgets/timeinput.py
index 0a23987bb0..3ae7e13e3f 100644
--- a/core/src/toga/widgets/timeinput.py
+++ b/core/src/toga/widgets/timeinput.py
@@ -42,9 +42,6 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        # Create a platform specific implementation of a TimeInput
-        self._impl = self.factory.TimeInput(interface=self)
-
         self.on_change = None
         self.min = min
         self.max = max
@@ -52,6 +49,9 @@ def __init__(
         self.value = value
         self.on_change = on_change
 
+    def _create(self) -> Any:
+        return self.factory.TimeInput(interface=self)
+
     @property
     def value(self) -> datetime.time:
         """The currently selected time. A value of ``None`` will be converted into the
diff --git a/core/src/toga/widgets/tree.py b/core/src/toga/widgets/tree.py
index 4c2b2c616e..a4d5ceb862 100644
--- a/core/src/toga/widgets/tree.py
+++ b/core/src/toga/widgets/tree.py
@@ -78,8 +78,6 @@ def __init__(
             defined.
         :param on_double_click: **DEPRECATED**; use :attr:`on_activate`.
         """
-        super().__init__(id=id, style=style)
-
         ######################################################################
         # 2023-06: Backwards compatibility
         ######################################################################
@@ -117,12 +115,16 @@ def __init__(
         self.on_activate = None
         self._data = None
 
-        self._impl = self.factory.Tree(interface=self)
+        super().__init__(id=id, style=style)
+
         self.data = data
 
         self.on_select = on_select
         self.on_activate = on_activate
 
+    def _create(self):
+        return self.factory.Tree(interface=self)
+
     @property
     def enabled(self) -> Literal[True]:
         """Is the widget currently enabled? i.e., can the user interact with the widget?
diff --git a/core/src/toga/widgets/webview.py b/core/src/toga/widgets/webview.py
index 740d830af2..64d5a641bd 100644
--- a/core/src/toga/widgets/webview.py
+++ b/core/src/toga/widgets/webview.py
@@ -44,13 +44,15 @@ def __init__(
         """
         super().__init__(id=id, style=style)
 
-        self._impl = self.factory.WebView(interface=self)
         self.user_agent = user_agent
 
         # Set the load handler before loading the first URL.
         self.on_webview_load = on_webview_load
         self.url = url
 
+    def _create(self) -> Any:
+        return self.factory.WebView(interface=self)
+
     def _set_url(self, url: str | None, future: asyncio.Future | None) -> None:
         # Utility method for validating and setting the URL with a future.
         if (url is not None) and not url.startswith(("https://", "http://")):
diff --git a/core/tests/app/test_widget_registry.py b/core/tests/app/test_widget_registry.py
index a5a25d96f8..0e5d567056 100644
--- a/core/tests/app/test_widget_registry.py
+++ b/core/tests/app/test_widget_registry.py
@@ -1,24 +1,15 @@
 import pytest
 
-import toga
 from toga.app import WidgetRegistry
 
+from ..utils import ExampleLeafWidget
+
 
 @pytest.fixture
 def widget_registry():
     return WidgetRegistry()
 
 
-# Create the simplest possible widget with a concrete implementation
-class ExampleWidget(toga.Widget):
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
-
-    def __repr__(self):
-        return f"Widget(id={self.id!r})"
-
-
 def test_empty_registry(widget_registry):
     assert len(widget_registry) == 0
     assert list(widget_registry) == []
@@ -28,7 +19,7 @@ def test_empty_registry(widget_registry):
 def test_add_widget(widget_registry):
     """Widgets can be added to the registry."""
     # Add a widget to the registry
-    widget1 = ExampleWidget(id="widget-1")
+    widget1 = ExampleLeafWidget(id="widget-1")
     widget_registry._add(widget1)
 
     assert len(widget_registry) == 1
@@ -37,7 +28,7 @@ def test_add_widget(widget_registry):
     assert widget_registry["widget-1"] == widget1
 
     # Add a second widget
-    widget2 = ExampleWidget(id="widget-2")
+    widget2 = ExampleLeafWidget(id="widget-2")
     widget_registry._add(widget2)
 
     assert len(widget_registry) == 2
@@ -48,12 +39,12 @@ def test_add_widget(widget_registry):
 def test_update_widgets(widget_registry):
     """The registry can be bulk updated."""
     # Add a widget to the registry
-    widget1 = ExampleWidget(id="widget-1")
+    widget1 = ExampleLeafWidget(id="widget-1")
     widget_registry._add(widget1)
 
-    widget2 = ExampleWidget(id="widget-2")
-    widget3 = ExampleWidget(id="widget-3")
-    widget4 = ExampleWidget(id="widget-4")
+    widget2 = ExampleLeafWidget(id="widget-2")
+    widget3 = ExampleLeafWidget(id="widget-3")
+    widget4 = ExampleLeafWidget(id="widget-4")
     widget_registry._update({widget2, widget3, widget4})
 
     assert len(widget_registry) == 4
@@ -67,8 +58,8 @@ def test_remove_widget(widget_registry):
     """A widget can be removed from the repository."""
     "Widgets can be added to the registry"
     # Add a widget to the registry
-    widget1 = ExampleWidget(id="widget-1")
-    widget2 = ExampleWidget(id="widget-2")
+    widget1 = ExampleLeafWidget(id="widget-1")
+    widget2 = ExampleLeafWidget(id="widget-2")
     widget_registry._update({widget1, widget2})
 
     assert len(widget_registry) == 2
@@ -82,7 +73,7 @@ def test_remove_widget(widget_registry):
 def test_add_same_widget_twice(widget_registry):
     """A widget cannot be added to the same registry twice."""
     # Add a widget to the registry
-    widget1 = ExampleWidget(id="widget-1")
+    widget1 = ExampleLeafWidget(id="widget-1")
     widget_registry._add(widget1)
 
     assert len(widget_registry) == 1
@@ -102,12 +93,12 @@ def test_add_same_widget_twice(widget_registry):
 def test_add_duplicate_id(widget_registry):
     """A widget cannot be added to the same registry twice."""
     # Add a widget to the registry
-    widget1 = ExampleWidget(id="widget-1")
+    widget1 = ExampleLeafWidget(id="widget-1")
     widget_registry._add(widget1)
 
     assert len(widget_registry) == 1
 
-    new_widget = ExampleWidget(id="widget-1")
+    new_widget = ExampleLeafWidget(id="widget-1")
 
     # Add the widget again; this raises an error
     with pytest.raises(
@@ -123,7 +114,7 @@ def test_add_duplicate_id(widget_registry):
 
 def test_setitem(widget_registry):
     """Widgets cannot be directly assigned to the registry."""
-    widget1 = ExampleWidget(id="widget-1")
+    widget1 = ExampleLeafWidget(id="widget-1")
 
     with pytest.raises(
         TypeError,
diff --git a/core/tests/style/pack/utils.py b/core/tests/style/pack/utils.py
index 185f2e132f..86c3f1f8d9 100644
--- a/core/tests/style/pack/utils.py
+++ b/core/tests/style/pack/utils.py
@@ -7,9 +7,23 @@
 
 class ExampleNode(Node):
     def __init__(self, name, style, size=None, children=None):
-        super().__init__(
-            style=style, children=children, applicator=TogaApplicator(self)
-        )
+        self._impl = Mock()
+        self._children = None
+
+        super().__init__(style=style, children=children, applicator=TogaApplicator())
+
+        ##############################################
+        # Backwards compatibility for Travertino 0.3.0
+        ##############################################
+
+        if not hasattr(self.applicator, "node"):
+            self.applicator.node = self
+            self.style._applicator = self.applicator
+            self.style.reapply()
+
+        #############################
+        # End backwards compatibility
+        #############################
 
         self.name = name
         self._impl = Mock()
diff --git a/core/tests/style/test_applicator.py b/core/tests/style/test_applicator.py
index b8f2e4bb9b..01a0594bf3 100644
--- a/core/tests/style/test_applicator.py
+++ b/core/tests/style/test_applicator.py
@@ -1,27 +1,12 @@
 import pytest
 
-import toga
 from toga.colors import REBECCAPURPLE
 from toga.fonts import FANTASY
+from toga.style import TogaApplicator
 from toga.style.pack import HIDDEN, RIGHT, VISIBLE
 from toga_dummy.utils import assert_action_performed_with
 
-
-# Create the simplest possible widget with a concrete implementation that will
-# allow children
-class ExampleWidget(toga.Widget):
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
-        self._children = []
-
-
-# Create the simplest possible widget with a concrete implementation that cannot
-# have children.
-class ExampleLeafWidget(toga.Widget):
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
+from ..utils import ExampleLeafWidget, ExampleWidget
 
 
 @pytest.fixture
@@ -154,3 +139,17 @@ def test_set_background_color(child, widget):
     widget.applicator.set_background_color(REBECCAPURPLE)
 
     assert_action_performed_with(widget, "set background color", color=REBECCAPURPLE)
+
+
+def test_deprecated_widget_argument(widget):
+    """The widget argument to TogaApplicator is deprecated."""
+    with pytest.warns(DeprecationWarning):
+        TogaApplicator(widget)
+
+
+def test_widget_alias_to_node(widget):
+    """Applicator.widget is an alias to applicator.node."""
+    applicator = widget.applicator
+
+    assert applicator.widget is widget
+    assert applicator.widget is applicator.node
diff --git a/core/tests/utils.py b/core/tests/utils.py
new file mode 100644
index 0000000000..1021c67cb7
--- /dev/null
+++ b/core/tests/utils.py
@@ -0,0 +1,26 @@
+import toga
+
+
+# Create the simplest possible widget with a concrete implementation that will
+# allow children
+class ExampleWidget(toga.Widget):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self._children = []
+
+    def _create(self):
+        return self.factory.Widget(interface=self)
+
+    def __repr__(self):
+        return f"Widget(id={self.id!r})"
+
+
+# Create the simplest possible widget with a concrete implementation that cannot
+# have children.
+class ExampleLeafWidget(toga.Widget):
+    def _create(self):
+        return self.factory.Widget(interface=self)
+
+    def __repr__(self):
+        return f"Widget(id={self.id!r})"
diff --git a/core/tests/widgets/test_base.py b/core/tests/widgets/test_base.py
index fb71b92f53..9052bdf095 100644
--- a/core/tests/widgets/test_base.py
+++ b/core/tests/widgets/test_base.py
@@ -1,6 +1,9 @@
+from unittest.mock import Mock
+
 import pytest
 
 import toga
+from toga.platform import get_platform_factory
 from toga.style import Pack
 from toga_dummy.utils import (
     EventLog,
@@ -11,22 +14,23 @@
     attribute_value,
 )
 
+from ..utils import ExampleLeafWidget, ExampleWidget
+
 
-# Create the simplest possible widget with a concrete implementation that will
-# allow children
-class ExampleWidget(toga.Widget):
+# Represent a hypothetical user-created widget class that does create and assign a valid
+# implementation, but doesn't do so in _create(). This is to assist with migration for
+# existing user code written before #2942 reorganized widget initialization.
+#
+# Right now this only issues a warning. Unfortunately it only works if the _impl is
+# set *before* super().__init__; any existing code that does so afterward will raise an
+# exception.
+class WidgetSubclassWithoutCreate(toga.Widget):
     def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
-        self._children = []
 
+        self.factory = get_platform_factory()
+        self._impl = self.factory.Widget(interface=self)
 
-# Create the simplest possible widget with a concrete implementation that cannot
-# have children.
-class ExampleLeafWidget(toga.Widget):
-    def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
 
 
 @pytest.fixture
@@ -911,6 +915,7 @@ def test_remove_from_non_parent(widget):
     other = ExampleWidget(id="other")
     child = ExampleLeafWidget(id="child_id")
     other.add(child)
+    EventLog.reset()
 
     assert widget.children == []
     assert other.children == [child]
@@ -1237,3 +1242,22 @@ def test_tab_index(widget):
 
     assert widget.tab_index == 8
     assert attribute_value(widget, "tab_index") == tab_index
+
+
+def test_one_reapply_during_init():
+    """Style's reapply() should be called exactly once during widget initialization."""
+
+    class MockedPack(Pack):
+        reapply = Mock()
+
+    ExampleWidget(style=MockedPack())
+    MockedPack.reapply.assert_called_once()
+
+
+def test_widget_with_no_create():
+    """Creating a widget with no _create() method issues a warning."""
+    with pytest.warns(
+        RuntimeWarning,
+        match=r"Widgets should create and return their implementation",
+    ):
+        WidgetSubclassWithoutCreate()
diff --git a/core/tests/window/__init__.py b/core/tests/window/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/core/tests/window/test_filtered_widget_registry.py b/core/tests/window/test_filtered_widget_registry.py
index d8c4af16c7..29ffc895f9 100644
--- a/core/tests/window/test_filtered_widget_registry.py
+++ b/core/tests/window/test_filtered_widget_registry.py
@@ -2,15 +2,7 @@
 
 import toga
 
-
-# Create the simplest possible widget with a concrete implementation
-class ExampleWidget(toga.Widget):
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self._impl = self.factory.Widget(self)
-
-    def __repr__(self):
-        return f"Widget(id={self.id!r})"
+from ..utils import ExampleLeafWidget
 
 
 # Create a box subclass with a reproducible repr
@@ -24,8 +16,8 @@ def make_window(win_id):
     win.content = ExampleBox(
         id=f"{win_id}.0",
         children=[
-            ExampleWidget(id=f"{win_id}.1"),
-            ExampleWidget(id=f"{win_id}.2"),
+            ExampleLeafWidget(id=f"{win_id}.1"),
+            ExampleLeafWidget(id=f"{win_id}.2"),
         ],
     )
     return win
@@ -155,7 +147,7 @@ def test_reuse_id(app):
 
     # Create a widget with the magic ID. The widget still isn't in the registry, because
     # it's not part of a window
-    first = ExampleWidget(id="magic")
+    first = ExampleLeafWidget(id="magic")
 
     assert "magic" not in app.widgets
     assert "magic" not in win_1.widgets
@@ -171,7 +163,7 @@ def test_reuse_id(app):
 
     # Create a second widget with the same ID.
     # The widget exists, but the registry is storing `first`.
-    second = ExampleWidget(id="magic")
+    second = ExampleLeafWidget(id="magic")
 
     assert "magic" in app.widgets
     assert "magic" in win_1.widgets
diff --git a/dummy/src/toga_dummy/utils.py b/dummy/src/toga_dummy/utils.py
index 2cb1ce3358..d5ab2e5f32 100644
--- a/dummy/src/toga_dummy/utils.py
+++ b/dummy/src/toga_dummy/utils.py
@@ -371,7 +371,14 @@ def assert_action_performed_with(_widget, _action, **test_data):
                             found = False
                     except AttributeError:
                         # No raw attribute; use the provided value as-is
-                        if data[key] != value:
+                        try:
+                            if data[key] != value:
+                                found = False
+                        ########################################################
+                        # Backwards compatibility for Travertino 0.3.0
+                        # Font.__eq__ throws an AttributeError against non-Fonts
+                        ########################################################
+                        except AttributeError:
                             found = False
                 except KeyError:
                     found = False
diff --git a/dummy/src/toga_dummy/widgets/base.py b/dummy/src/toga_dummy/widgets/base.py
index 93743330f6..186f3fb9a3 100644
--- a/dummy/src/toga_dummy/widgets/base.py
+++ b/dummy/src/toga_dummy/widgets/base.py
@@ -7,7 +7,6 @@ class Widget(LoggedObject):
     def __init__(self, interface):
         super().__init__()
         self.interface = interface
-        self.interface._impl = self
         self.container = None
         self.create()
 
diff --git a/gtk/src/toga_gtk/widgets/base.py b/gtk/src/toga_gtk/widgets/base.py
index c1868f1aa2..7363341459 100644
--- a/gtk/src/toga_gtk/widgets/base.py
+++ b/gtk/src/toga_gtk/widgets/base.py
@@ -9,7 +9,6 @@ class Widget:
     def __init__(self, interface):
         super().__init__()
         self.interface = interface
-        self.interface._impl = self
         self._container = None
         self.native = None
         self.style_providers = {}
@@ -24,9 +23,6 @@ def __init__(self, interface):
         self.native.set_name(f"toga-{self.interface.id}")
         self.native.get_style_context().add_class("toga")
 
-        # Ensure initial styles are applied.
-        self.interface.style.reapply()
-
     @abstractmethod
     def create(self): ...
 
diff --git a/iOS/src/toga_iOS/widgets/base.py b/iOS/src/toga_iOS/widgets/base.py
index 59cb4f241b..4692a08286 100644
--- a/iOS/src/toga_iOS/widgets/base.py
+++ b/iOS/src/toga_iOS/widgets/base.py
@@ -9,12 +9,10 @@ class Widget:
     def __init__(self, interface):
         super().__init__()
         self.interface = interface
-        self.interface._impl = self
         self._container = None
         self.constraints = None
         self.native = None
         self.create()
-        self.interface.style.reapply()
 
     @abstractmethod
     def create(self): ...
diff --git a/textual/src/toga_textual/factory.py b/textual/src/toga_textual/factory.py
index b737aed521..d41f6da7fa 100644
--- a/textual/src/toga_textual/factory.py
+++ b/textual/src/toga_textual/factory.py
@@ -3,8 +3,7 @@
 from . import dialogs
 from .app import App
 from .command import Command
-
-# from .fonts import Font
+from .fonts import Font
 from .icons import Icon
 
 # from .images import Image
@@ -50,7 +49,7 @@ def not_implemented(feature):
     "not_implemented",
     "App",
     "Command",
-    # "Font",
+    "Font",
     "Icon",
     # "Image",
     "Paths",
diff --git a/textual/src/toga_textual/fonts.py b/textual/src/toga_textual/fonts.py
new file mode 100644
index 0000000000..fa9d3f0e6c
--- /dev/null
+++ b/textual/src/toga_textual/fonts.py
@@ -0,0 +1,2 @@
+class Font:
+    def __init__(*args, **kwargs): ...
diff --git a/textual/src/toga_textual/widgets/base.py b/textual/src/toga_textual/widgets/base.py
index ce10ebad3e..dd2f0a6693 100644
--- a/textual/src/toga_textual/widgets/base.py
+++ b/textual/src/toga_textual/widgets/base.py
@@ -32,7 +32,6 @@ def scale_out_vertical(self, value):
 class Widget(Scalable):
     def __init__(self, interface):
         self.interface = interface
-        self.interface._impl = self
         self.container = None
         self.create()
 
diff --git a/web/src/toga_web/widgets/base.py b/web/src/toga_web/widgets/base.py
index 1f721aade0..e7c9c565d1 100644
--- a/web/src/toga_web/widgets/base.py
+++ b/web/src/toga_web/widgets/base.py
@@ -4,7 +4,6 @@
 class Widget:
     def __init__(self, interface):
         self.interface = interface
-        self.interface._impl = self
         self._container = None
 
         self.create()
diff --git a/winforms/src/toga_winforms/widgets/base.py b/winforms/src/toga_winforms/widgets/base.py
index 3f0d2cdf86..cc683bd00e 100644
--- a/winforms/src/toga_winforms/widgets/base.py
+++ b/winforms/src/toga_winforms/widgets/base.py
@@ -46,7 +46,6 @@ class Widget(Scalable, ABC):
 
     def __init__(self, interface):
         self.interface = interface
-        self.interface._impl = self
 
         self._container = None
         self.native = None
@@ -64,8 +63,6 @@ def __init__(self, interface):
         #    at System.Windows.Forms.TabControl.GetTabPage(Int32 index)
         self.native.CreateGraphics().Dispose()
 
-        self.interface.style.reapply()
-
     @abstractmethod
     def create(self): ...