Delightful apps & games for the whole family
A small, independent studio crafting apps people love to come back to.
What We Make
Box of Otters ships three apps, all free to download on the App Store and Google Play: Block Craze, a block-blast puzzle game; Gambits Edge, a chess board scanner and AI coach; and BJJ Tracker, a Brazilian Jiu-Jitsu training log with automatic gym check-in.
A relaxing block-blast puzzle. Drag, drop, and clear the grid across 100 levels and 10 worlds, with no timers and no pressure.
Play Block Craze →
Scan any chess board with your camera. Instant Stockfish analysis, plain-language coaching, and trap detection, all of it offline.
Discover Gambits Edge →
Your Brazilian Jiu-Jitsu journey, logged automatically. Arrive at your gym and the class records itself, belts and stripes included.
Visit BJJ Tracker →Who We Are
Box of Otters is an independent app studio building family-friendly apps and games for iOS and Android. We work across gaming, education, and sports — from casual puzzle games to focused tools for chess players and grapplers.
Our approach is simple: build apps that are easy to pick up, genuinely useful or fun, and free of the dark patterns that clutter so many mobile experiences. Every app we ship — Block Craze, Gambits Edge, and BJJ Tracker — is made by a small team that cares about craft, reads every piece of feedback, and ships steady improvements.
Questions
Straight answers about the studio and the three apps it makes.
Box of Otters is an independent mobile app studio that builds and publishes its own family-friendly apps and games for iOS and Android. It is not a publisher or an agency. Every app on this site was made in-house. It currently ships three apps: Block Craze, Gambits Edge, and BJJ Tracker.
Three. Block Craze is a free block-blast puzzle game with 100 levels across 10 worlds. Gambits Edge is a chess board scanner and AI coach that reads any board through your camera and explains the best move. BJJ Tracker is a Brazilian Jiu-Jitsu training log that checks you in automatically when you arrive at your gym.
All three apps are free to download. BJJ Tracker is free. Block Craze is free to play, with an optional one-time $2.99 purchase to remove ads. Gambits Edge has a free tier with three board scans per month plus a daily ad-bonus scan, and an optional Pro subscription for unlimited scanning.
Yes. Block Craze, Gambits Edge, and BJJ Tracker are all live on Google Play as well as the Apple App Store.
Yes. Gambits Edge runs its board scanning and Stockfish analysis entirely on-device, so it works with no internet connection. BJJ Tracker works offline and keeps your training data on your device. Block Craze gameplay also runs on-device.
No. None of the three apps requires you to create an account to use its core features.
Email hello@boxofotters.com for anything studio-related, or gambitsedge@boxofotters.com for questions specific to Gambits Edge.
Get In Touch
Questions, feedback, or just want to say hi? We'd love to hear from you.
hello@boxofotters.com