Sumi: Zen Sudoku
Quiet sudoku. Daily practice.
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
墨 Sumi is sudoku, stripped of noise.
No leaderboards. No streaks that shame you. No timers ticking in your face. Just a nine by nine grid, drawn in warm ink on washipaper, waiting for your next move.
FIVE LEVELS OF PRACTICE
Five difficulties, from your first quiet solve to the edge of mastery. Each level is a different conversation with the grid.
1. Easy and Medium: unhurried, forgiving.
2. Hard: where focus begins to matter.
3. Master and Edo: for those who have earned stillness.
A DAILY HABIT
Open Sumi each day. Solve one puzzle. Watch your streak grow, your times sharpen. The Practice Log tracks your progress with a clean improvement curve. No gamification. Just the graph.
YOUR SEASON, YOUR PALETTE
Choose a season at first launch: Spring, Summer, Autumn, or Winter. Each shifts the accent colour that breathes through the interface. Change it anytime in Settings.
SUMI PRO - Unlock the full practice:
1. The Library: a curated collection of passages from Zen masters, philosophers, and makers. One surfaces each day.
2. Design Zen Sudoku: build a print-ready A5 puzzle book. Pick your difficulty mix, your paper colour, your ink. Export as PDF and
print.
3. Full improvement history and personal bests at every difficulty.
4. No Ads
One-time purchase. No subscription. No renewal.
ABOUT THE NAME
墨 (sumi) is the ink used in traditional Japanese calligraphy and sumi-e painting. Ground from a solid inkstick, mixed with water, applied with patience. The name describes the aesthetic: deliberate, unhurried, lasting.
Ink on paper. No chrome. No noise. Nine by nine, every day.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Easier on the eyes.
Pencil marks are bigger now. The small candidate numbers inside each square have grown, so a square full of notes is easy to read at a glance without squinting or zooming.
Small polish under the hood too, so puzzles keep loading quickly.
The developer, Karan Sharma, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Location
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Location
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Karan Sharma
- Size
- 81.8 MB
- Category
- Puzzle
- Compatibility
Requires iOS 18.2 or later.
- iPhone
Requires iOS 18.2 or later. - iPad
Requires iPadOS 18.2 or later. - Mac
Requires macOS 15.2 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.2 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Contains
Advertising
- In-App Purchases
Yes
- Sumi Pro $2.99
- Copyright
- © Karan Sharma

