Here is a list of my favorite android apps. Feel free to post your own.
- F-Droid (app store)
- RethinkDNS (firewall/dns)
- KeePassDX (offline password manager)
- NewPipe or FreeTube (YouTube)
- Ghost Commander (file manager)
- Heliboard (keyboard)
- Termux (linux terminal emulator)
- AntennaPod (podcasts)
- Aegis (2 factor authentication)
- Mull (firefox based web browser)
- OsmAnd (offline navigation)
- Trail Sense (hiking companion)
Firewall -> universal firewall rules. Or you can run it in dns mode only if you dont want to block any apps.