SudokuFlow

Most Sudoku apps guess at difficulty. SudokuFlow grades every puzzle by the techniques a human actually needs to solve it — so "Hard" means hard, every time. DIFFICULTY THAT ADAPTS Your flow level is a single rating from 0 to 1000. Win comfortably and it rises; struggle and it eases off. The next puzzle you're offered sits just above your comfort level — interesting, never a wall. FIVE HONEST BANDS Easy, Medium, Hard, Expert and Master. Every puzzle has exactly one solution and a symmetric grid — generated on your device, never downloaded. HINTS THAT TEACH Stuck? A hint doesn't just drop in a digit. It names the technique, explains why it works in that cell, and lets you place the number yourself. You finish the puzzle having learned something you can use on the next one. A DAILY RITUAL One puzzle a day, the same grid for everyone, ramping from a gentle Monday to a Sunday that bites. Solve it to keep your streak alive. PROGRESS WORTH WATCHING Your flow level, current and longest streak, flawless solves, your best time in every band, and an activity map of every day you've played. BUILT TO STAY OUT OF THE WAY Pencil marks that clean themselves up as you place digits. Undo, erase, and matching-number highlighting. An optional mistake limit and timer. Haptics. Light and dark themes that follow your system. YOURS, OFFLINE No account. No sign-up. No servers. Your puzzles, progress and statistics live on your device and never leave it. SUDOKUFLOW PRO — ONE PAYMENT, FOREVER • Remove all ads • Unlimited teaching hints (free: 3 a day) • The full daily archive — go back and clear the days you missed • Master difficulty • Support an indie developer No subscription. Buy it once, keep it forever.