I never imagined I'd like playing Tetris on the command line, on a terminal on my phone (termux), but here I am!
I couldn't find any Tetris app on fdroid, and just checked if pkgs had one. Lo and behold! It asked me to run pkgs install vitetris, and when I did, the tetris command was there to launch the game.
It's a two step process, as opposed to just launching an app, but it is very lightweight, no tracking, and FOSS.
For anyone with termux already installed and feeling a bit nostalgic, might be worth trying it out.
It's wild that there aren't any FOSS Tetris games for Android that have been updated this decade.
that's a good thing. Tetris is tetris.You code in all the rules, and you're done. any updates made in the last decade would be the types that "improve the user experience" such as allowing you to pay real money to double your chances of getting the l tetromino, a subscription which would remove the unskippable ads you get after every game, and a microtransaction that allows you to pay to play more than one game per day
Sometimes an app needs to be updated to work properly with the latest operating system. I wouldn't say it's great to have no updates for a decade.
Well if you want an uptodate FOSS Tetris https://www.f-droid.org/packages/com.serwylo.retrowars/
Except tetris is not as stable as you might think
The current ruleset uses vastly different rotation systems than the games in the early days, or Akira's TGM series.
Moreover, you can add new features without it being pay 2 win (or even paid), like tetr.io does: ranked matches, leaderboards, tournaments, social interaction, etc... They can also make new rules, like how they recently removed passthrough in online matches.
Games really don't need to be updated often.