Sudoku Ultra app icon

Sudoku Ultra

A fresh daily Sudoku with five genuine difficulty levels. Pencil marks, limited hints, streaks and best times. Play completely offline. Free on Android.

Free Android PEGI 3 by netAdapt

Real difficulty.
Real progress.

Every tier is defined by the solving techniques it demands — not just how many cells are empty. Learn new patterns as you climb.

One daily board per difficulty, the same for every player worldwide. Solve any of them to keep your streak alive.

Download Sudoku Ultra. Solve today. Come back tomorrow.

Sudoku Ultra showing a puzzle in progress

Free

Android · PEGI 3 · One-time IAP removes ads

Google Play

§ 01 — Difficulty

Five tiers.
From naked singles to diabolical.

Each level introduces real techniques. Your stars and best times are tracked separately so you can watch yourself improve.

  • Easy

    Naked singles only

  • Medium

    Hidden singles & pairs

  • Hard

    Locked candidates & triples

  • Expert

    X-Wings, Y-Wings, Swordfish

  • Diabolical

    For solvers who want a fight

§ 02 — Daily & practice

One new board a day.
Unlimited more whenever you want.

The daily keeps the ritual alive. Extra puzzles let you grind a specific difficulty as long as you like.

  • Daily

    Same puzzle worldwide

    Everyone gets the identical daily board at each difficulty. Compare notes, chase the same best time.

  • Streaks

    Keep the chain going

    Solve any daily puzzle (any tier) once per day to maintain your streak. Long streaks feel great.

  • Extras

    Endless random boards

    Already cleared today? Jump into unlimited fresh random puzzles at any unlocked difficulty. No limits.

§ 03 — Tools & customisation

Pencil marks.
Smart hints. Your symbols.

Everything you need for serious solving, nothing that gets in the way.

  • Notes

    Pencil & candidates

    Tap to toggle small candidate numbers. Clean, readable, and they stay out of your way when solving.

  • Help

    Limited hints

    A gentle hint system that points you in the right direction without solving the puzzle for you.

  • Look

    Four symbol sets

    Classic 1–9, letters A–I, shapes or zodiac symbols. Switch any time. Light and dark themes too.

§ 04 — Progress

Stars, times and streaks.
Watch yourself get better.

Three clear signals of improvement, all visible without digging through menus.

  • ★★★

    Star ratings

    Faster, cleaner solves earn more stars on each board. Your best star count per difficulty is saved.

  • Time

    Personal bests

    Your fastest solve time at every difficulty is recorded and shown. Beat your record on any board.

  • Streak

    Daily consistency

    The streak counter rewards showing up. Optional gentle reminders help you keep the habit without pressure.

§ 05 — Frequently asked

Questions, answered.

For app-store searchers and curious humans.

Is Sudoku Ultra free?
Yes. Sudoku Ultra is free on Google Play with an optional one-time purchase that removes ads forever. No subscriptions, no energy system.
What difficulty levels are there?
Five tiers based on required techniques: Easy (naked singles only), Medium (hidden singles and pairs), Hard (locked candidates and triples), Expert (X-Wings, Y-Wings and Swordfish) and Diabolical for the bravest solvers.
How does the daily puzzle work?
One new board per difficulty per day, the same puzzle for everyone worldwide at each tier. Solve any daily (any difficulty) to keep your streak going.
Can I play more than the daily?
Yes. Tap Extra Puzzles on any difficulty row for unlimited randomly generated boards at that exact difficulty. Practice as much as you like.
Is it on iPhone or iPad?
Sudoku Ultra is currently Android-only.
What do the symbols do?
You can switch the board between classic numbers, letters (A–I), shapes or zodiac signs. Great for accessibility or just a fresh look.
Does it work completely offline?
Yes. Install and play anywhere. Your streaks, best times and solves are stored on your device. Optional daily reminders can be enabled in settings.
Who makes Sudoku Ultra?
netAdapt Ltd, an independent UK software studio in Newbury, Berkshire. We have been building games and apps since 2001.