About CageDoku

CageDoku is a calm, ad-free Killer Sudoku app with seven more logic variants, made by one developer in Kyiv, Ukraine.

Who makes it

CageDoku is designed, built and published by Andrew Boyko, an independent developer (sole proprietor) based in Kyiv. Write to support@killersudoku.andrewboyko.name; every message is read by the person who makes the app.

Why it exists

Most Killer Sudoku apps interrupt you with ads or give a hint that just shows a digit. CageDoku was built to be the opposite: no ads at any point, and hints that name the technique, highlight the cells and explain the reasoning.

How the puzzles are made

Puzzles are generated by the app’s engine and rated by the hardest human technique they need: unique cage combinations and singles at Gentle, the 45 rule and combination elimination at Moderate and Tough, and pairs, triples, fish and chains at Diabolical and Extreme. Every puzzle is designed to be solvable by logic, with no guessing.

What is in the app

• Eight variants: Killer, Classic, Thermo, Arrow, Kropki, Sandwich, Chess (anti-knight) and Diagonal.
• Five levels from Gentle to Extreme.
• Daily 3 with streaks: a Killer, a rotating variant and a quick 6×6.
• Six themes, dark and light mode.
• Free to play; optional Pro (monthly, yearly or lifetime) adds unlimited hints and puzzles, statistics, streak freezes, all themes and PDF export.

Available on Google Play and in the browser. The iOS version is in App Store review. The privacy policy explains what data the app handles (very little).

Press

Logos, screenshots and boilerplate are on the press page.

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