Help for experimental versions

resources/help.txt

@@ -112,10 +112,21 @@ Usage:
 
 Platform-specific usage:
     $ tns platform add android [--frameworkPath <File Path>] [--symlink]
-    $ tns platform add ios [--frameworkPath <File Path>] [--symlink] 
+    $ tns platform add android[@<Version>] [--frameworkPath <File Path>] [--symlink]
+    $ tns platform add ios [--frameworkPath <File Path>] [--symlink]
+    $ tns platform add ios[@<Version>] [--frameworkPath <File Path>] [--symlink]
 
 Configures the current project to target the selected platform. 
 
+<Version> is any available version published in npm.
+You can get out of the box 0-day support for native new native platforms.
+Because NativeScript exposes unmodified native APIs and UI components, you can use the latest native APIs and new UI components when Apple, Google or Microsoft updates their mobile platforms.
+When this happens we release new experimental version of NativeScript runtime. When $ tns platform add <Platform> command is executed, NativeScript CLI downloads the latest stable version.
+If you want to use experimental version or any other version just run $ tns platform add <Platform>@<Version>
+To list all available versions for android platform run $ npm view tns-android versions. To list only experimental versions for android platform run $ npm view tns-android dist-tags.
+To list all available versions for ios platform run $ npm view tns-ios versions. To list only experimental versions for ios platform run $ npm view tns-ios dist-tags.
+
+
 <File Path> is the complete path to a valid npm package or a directory that contains a NativeScript runtime for the selected platform. 
 
 When you add a target platform, the NativeScript CLI adds a corresponding platform-specific subdirectory under the platforms directory. This platform-specific directory contains the necessary files to let you build your project for the target platform.