This is the collection of small libraries I wrote mostly for convenience while I work on iOS projects. These small libraries has helped me tremendously, so I guess I want to share it to help other people. This may or may not suit your needs, so use it at your own disposal.
Download this as zipped file or clone it to your project. This library contains Objective-C code as well as Swift code. If you're working with the Swift project, to include all the Objective-C code, you only need to create Objective-C bridging header and import the "CommonLibrary.h". All the Swift library will be automatically ready to use for you.