AnkiDroid (Anki - Spaced repetition app)
AntennaPod (Podcasts app)
Coffee (quicktile alowing adjusting how long will the display will stay awak)
NetGuard (VPN to control app internet access & domain based ad blocking)
Newpipe (alternative youtube & other media sites frontend)
OsmAnd (Navigation based on Open Street Map)
Sky Map (google's sky map)
Telegram FOSS (Telegram client)
VLC (media player)
WiFiAnalyzer