This library is a simple interface to facilitate the way to graph points in a Cartesian plane, additionally you can create simple polygons, it was done with the native app of Canvas.
Android-Week-View is an android library to display calendars (week view or day view) within the app. It supports custom styling.
Features:
Chameleon is a CSS like framework for Android. Chameleon can read styles in JSON format and apply them on views in Android. Not only can you choose from the variety of styles provided by the library but also add your own styles by changing just one file.
The icing on the cake is, once set up, themes can be updated without pushing a new version of your app to the playstore. So, your users can see your changes on the fly.