A collective list of free APIs

An Android library for managing images and the memory they use.

Source code for the second edition of Head First Android Development

Reactive motion for Android. Deprecated; please use the Motion library in Material Components for Android instead: https://material.io/develop/android/theming/motion/.

A library for converting Adobe AE shape based animations to a data format and playing it back on Android and iOS devices.

Event bus for Android and Java that simplifies communication between Activities, Fragments, Threads, Services, etc. Less code, better quality.

Android image spannable on multi autocomplete text view

Use the GPIO pins on the Raspberry Pi without running as root

Apache Spark - A unified analytics engine for large-scale data processing

Serial I/O over bluetooth for NodeJS

EventBus for Android Wear devices.

Fast barcode scanning library for Android apps (including demo app)