System icons (Material Design)
System icons symbolize common actions, files, devices, and directories.
App Icon Sizes · phonegap/phonegap Wiki · GitHub
access core functions on Android, iPhone and Blackberry using JavaScript - phonegap/phonegap
Android (4.1) Icon Size Guide Made Simple
What are Android Icon Sizes? Our icon design team provide this guide on Android Launcher Icon Sizes, Action Bar Icons, Contextual & Notification Icons sizes