I'm the developer of rdx, a mildly popular ad-free, privacy and user friendly Reddit client. This time, I made something for a very specific use case: solving chess puzzles with no internet.
Why? Well, my Wi-Fi is terrible in the bathroom—and that's where I do some of my best thinking. I tried printing out “mate in X” puzzles to solve offline, but they weren’t fun without interaction. So I built OffChess.
OffChess is an iPhone/Android app that contains over 100,000 chess puzzles, fully offline and completely ad-free. You can solve puzzles by category (Mate in 1/2/3/4/5, tactics like pins/forks/skewers, or openings like Sicilian/French, etc). You gain or lose points based on how you perform, so there's a light rating system to keep things engaging.
No accounts, no tracking, no monthly subscriptions, no internet required. Just pure, old-school tactical chess training, wherever you are.
You can check out the iPhone/iPad app at https://apps.apple.com/us/app/chess-puzzles-offchess/id67447... or the Android app at https://play.google.com/store/apps/details?id=com.offchess
Would love feedback, bug reports, or suggestions.
Thanks!
There's no login required since the app uses Google Play Billing on Android and App Store billing on iOS. That also means purchases are tied to the Google account used to buy the app, so unfortunately they can't be shared across different accounts.
I hate the annoyance of apps forcing you to create an account before you even try them and that's exactly why I kept it simple and login-free. But yeah, the trade-off is stuff like what you pointed out. To balance that, I made it a one-time low-cost purchase instead of a subscription. Hope that makes it fair.
I don't have hand-to-hand experience with Google Play, but quite a few of those billing platforms offer "discount codes." So to help the GP commenter, I would imagine they could email you from their purchasing Google account and ask for 100% off codes for their other Google account addresses
I don't know how to help the sibling comment, short of you just straight-up making them a custom .apk without Play Billing. FWIW, it's actually absolutely painless to host your own f-droid repository <https://gitlab.com/fdroid/fdroidserver#what-is-f-droid-serve...>. It's marked AGPL but despite its name one doesn't need to run that package to host a repo, just $($HOMEBREW_PREFIX/bin/fdroid update --verbose --create-metadata -W error) and then $(rsync -Pav --delete ./repo/ your-awesome-host:/repo/)
It's so painless you could even do that per user, as in lucb1e-fdroid.example.com or lucb1e-a6d7c104-e9b1-4ddc-ad5a-470e51bb5069.example.com