itch.io - An online game marketplace and community.
Blockinger - An open source Tetris clone for Android.
GOG.com - DRM-free game store, selling both new and old titles. No clients required.
NullpoMino - NullpoMino is an open-source action puzzle game that works on the Java platform.
Ubisoft Club - Ubisoft Club app enables you to get updates about your favorite games timely.
Good Old Tetris - Play Tetris Online. The game that will never get old.