ProviderPreference, shared preferences accross processes built on ContentProvider

ColorPicker, a color picker widget easy to use, thanks to Daniel Nilsson

CropImage, a beautiful image cropping activity from AOSP Camera

QuickAction, a useful and pretty quick action implement on all Android versions, thanks to Lorensius. W. L. T

OutlineTextView, a TextView whose text has borders to increase readability

Styles and themes based on Android Holo theme, available for all Android versions