Messenger++ is a multi-protocol instant messaging client for Android. It features multi-protocol support (currently: XMPP, Facebook(XMPP), Google Talk(XMPP), VK, SMS) + audio calls if supported by the protocol. The UI is optimized for tablets. It is a Maven-based project with Robolectric tests built by Travis CI.
Slidematch is a media rating, contextual retrieval, peer recommendation, and library management system for music, video, movie, and book impressions. It adds value to your existing media player by enabling you to easily record detailed impressions, retrieve content appropriate to what you are currently doing, and interact with friends.
Lifebox is a fast, lightweight, social photo and video gallery application that is designed to organize large amounts of media. It is able to differentiate between original and modified photos so you can upload your entire library to your server and highlight your favorite photos and videos into albums to share with friends. Lifebox also makes a distinction between albums and rolls, so a single photo or video can be part of multiple albums but only one roll. It extracts data from EXIF tags and XMP sidecars, making it compatible with the data from programs like Adobe Lightroom, Picassa, and iPhoto. Lifebox is social in that people and objects can be tagged, and they will receive an email when this happens. It supports authentication, so you can control who has access to what photo.