RxJava – Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM.

Termux - a terminal emulator application for Android OS extendible by variety of packages.

A libre lightweight streaming front-end for Android.

A Java serialization/deserialization library to convert Java Objects into JSON and back

A free, secure and open source app for Android to manage your 2-step verification tokens.

Free and open log management

Material Design Music Player

A podcast manager for Android

Lightning fast, open-source, < 250kb Android launcher

Unofficial, FOSS-friendly fork of the original Telegram client for Android

Download apks from Google Play Store

An open source multi-modal trip planner

Slide is an open-source, ad-free Reddit browser for Android.

An Unsplash Client

APK Downloader for Google Play

Simple Galley App for Android, with lovely Material Design.

Eclipse hawkBit™

Another ugly tower defense for Android

Simple Android app for sharing links on Shaarli.