Built a free offline chess puzzle app, themed puzzles, progress tracking, and puzzle rush mode

Hey everyone,

I've been working on a chess puzzle app and wanted to share it with this community since you'd be the best people to give real feedback.

The app is called Chess Puzzles, it's completely offline, no account needed, and free.

Here's what it has:

A large library of puzzles organised by tactical themes (pins, forks, discovered attacks, etc.), so you can deliberately train weak spots
Random puzzle mode for quick sessions when you just want to solve
Puzzle Rush: timed mode to test how fast you can spot tactics under pressure
Puzzle history so you can revisit what you've solved
Progress analytics: shows which themes you're struggling with so you know where to focus
Achievements to keep motivation up across sessions
The idea was simple: chess.com and Lichess are great, but they require an internet connection. I wanted something you could grind on a commute or flight without needing a connection.

Would love honest feedback, especially from stronger players, on whether the puzzle quality and difficulty range feel right.

Playstore - https://play.google.com/store/apps/details?id=com.anonymous.offlinechesspuzzles
AppStore - http://apps.apple.com/us/app/chess-puzzles-tactics-train/id6763496867