Sudoku Collector

From Naked Singles to Bowman's Bingo — 79 techniques across 8 tiers, every puzzle named for the move it teaches. 4,100 in your pocket.

You've solved a thousand Sudoku puzzles. Now learn how the hard ones really crack — and bring the hard ones with you.

Sudoku Collector teaches you the techniques expert solvers use — not by grinding, but by guiding. Every puzzle is named for the technique it teaches: Naked Pair, X-Wing, Swordfish, ALS Chain, all the way up to Bowman's Bingo and Pattern Overlay. Choose Guided mode and the app walks you through hint trains that reveal each step in plain language. Switch to Challenge or Zen mode when you're ready to fly solo.

BRING YOUR OWN PUZZLES Found a hard puzzle in a magazine, on a website, in a friend's screenshot? Tap it onto a grid or paste the 81-character string — the app validates exactly-one-solution, classifies it against the same 79-technique solver that drives the built-in packs, and lands it in your Dossier. From there you Play it with the full Train hint sequence, watch the optimal solve as a filmstrip ("How to Solve"), or play it again as a fresh visual variant. No other Sudoku app on the App Store teaches imported puzzles with the same machinery as its first-party content.

WHAT'S INSIDE • 8 tiers, 79 named techniques across 12 families — Foundation, Intersections, Subsets, Fish, Wings, Single-Digit Chains, Multi-Digit Chains, Colouring, Uniqueness, Almost Locked Sets, plus Forcing and Exotic for the deep end. From Full House and Naked Single all the way to ALS Chain, SK-Loop, Exocet, Tridagon, Kraken Fish, and Bowman's Bingo. • A growing curated library of 82 packs — 69 single-technique drill packs, 8 family packs (Subsets, Fish, Wings, Unique Rectangles, Forcing, and more), and 5 mixed-tier packs. Every pack carries a calibrated learning curve: 50 hand-picked puzzles, every one chosen for what it teaches. New packs land over the air without app updates. • Same seed, fresh board every replay — under the hood every puzzle has trillions of visual variations, so a "Replay" gives you a new-looking grid every time. The library never feels small. • Your Dossier — your personal collection of puzzles you imported from the world, organized in folders, replayable forever, every one taught by the same engine as the built-in packs. • Guided hint trains — plain-language explanations of why each move is the move. The solver runs against your live board on every tap, so hints are never stale even if you solved part of the puzzle a different way. • A board built for chain solvers — color whole cells, color individual candidates inside a cell, and draw strong or weak links between candidates right on the board. Chain notation as a working surface, not a notebook. • Daily puzzles tuned to your level — twelve daily slots across the tiers, with a customizable difficulty range so you don't waste your day on six puzzles that are too easy and three that are too hard. The app gently nudges your range upward as you grow. Auto mode reads your trail progress; Custom mode lets you set the range yourself. • Accomplishments — a career wall, solver-identity trophies, and per-tier milestone tracking. • Filmstrip replay — at the end of every solve, watch your own moves play back as a victory parade, frame by frame. The same filmstrip view powers "How to Solve" by feeding it the optimal solver path instead of your moves — so you can study before you play, then watch yourself crack it after. • A deliberately minimal board — three themes (light, dark cool, dark warm) for everything around the board; the puzzle surface stays clean in all three so nothing competes with the logic.

WHO IT'S FOR For Sudoku players who've plateaued at "intermediate" and want a path through the hard stuff — and for the chain-solver crowd who've never had an app that respects how they actually work. Bring the puzzle you can't crack from anywhere; the app meets you on it.

The app works entirely offline; new puzzle packs ship over the air when you're online (and you can turn that off too), but nothing about how you play ever leaves your phone.