About Box of Otters

Box of Otters is an independent mobile app studio. It designs, builds, and publishes its own apps for iPhone, iPad, and Android. There are three of them: Block Craze, Gambits Edge, and BJJ Tracker. All three are free to download.

The studio is not a publisher, an agency, or a white-label shop. Nothing here was licensed in or contracted out. The same small team writes the code, draws the art, answers the support email, and ships the updates.

Three apps, three different problems

The catalogue looks scattered until you look at what each app actually does. A puzzle game, a chess tool, and a jiu-jitsu log have nothing in common on the surface. What they share is a specific kind of friction the studio wanted gone.

Block Craze solves boredom without demanding anything back. No timer, no energy meter, no daily login streak nagging you to return. You drag blocks onto a grid, fill rows and columns, and they clear. There are 100 levels across 10 worlds if you want structure, and an endless mode if you do not.

Gambits Edge solves a problem every improving chess player knows: you finish a game, you sense you went wrong somewhere, and reconstructing the position by hand to analyse it is more work than the insight is worth. Point a camera at the board instead. The app reads the position, runs Stockfish on it, and explains in plain language why a move is strong rather than handing you a number. Trap detection and opening recognition run alongside it. The whole thing works on the device, with no signal required, which matters in a club basement or a park.

BJJ Tracker solves the quietest problem of the three. Grapplers train for years and remember almost none of it, because logging a class after a hard session is the last thing anyone wants to do. So the app does it. Set your home academy once, and arriving at the gym triggers the check-in. One tap confirms whether it was gi, no-gi, drilling, open mat, a seminar, or a competition. Belts and stripes, technique library, progress charts, tournament record, and a separate profile for every training member of a household follow from there.

Block Craze

Free block-blast puzzle. 100 levels, 10 worlds, no timers.

Gambits Edge

Scan any chess board. Stockfish analysis and coaching, offline.

BJJ Tracker

Automatic gym check-in. Belts, stripes, and every class logged.

What we will not ship

Most of what makes mobile apps unpleasant is deliberate. Someone chose the interstitial ad that fires mid-move. Someone chose the countdown timer on a discount that resets forever. Those choices get made because they measure well in the short term.

The rules here are narrow and specific. No ad interrupts an active session. No app manufactures urgency it does not have. No core feature sits behind an account, because an account is a data-collection request dressed up as convenience. Nothing is sold to a data broker.

Studio facts

Get in touch

Bug reports, feature requests, and general mail all reach a person. Email [email protected] for anything studio-related, or [email protected] for questions specific to Gambits Edge. More answers are on the FAQ.