F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
Showly
an open source TV Shows & Movies tracker app that works with Trakt.
Why is tmdb better than trakt for you? I don’t know much about either service.
Trakt is a commercial service. TMDb is not.