It's recommended to create account and login in it after install to update the app (since there's no updates there). Since account can be potentially banned I recommend having separate one (if you have one with legit purchases, etc.).
Thx to Chess Odyssey for files.
https://1fichier.com/?89zpzcbdlbav7ex5dlz2
https://buzzheavier.com/f/GVCVtaaf0AA
https://rutracker.org/forum/viewtopic.php?t=6562877 (only DB)
They probably can but only after manual analysis.
Who is this Linus Sex Tips and what he did?
Okay, now seriously, I know who he is but I'm too lazy to check what he did.
You can make it FOSS and still have some sort of subscription for syncing between devices for example. Tasks.org did it like that.
Not to mention that you can run something on donations like lichess or F-Droid and have some extra money.
I don't wanna take part into all that discussion I'm more interested in why there's so much hype around this app. It's beautiful and stuff but not open-source and I bet there's no gamechanging features.