A little help.
Back to the grid.

Divide the grid into rectangles so that each one holds exactly one number, and that number is its area. Drag from one cell to another to draw a rectangle; when it fits, it takes its color. Tap a rectangle to remove it. Every puzzle has exactly one solution, reached by logic alone. The app’s How to play shows it in a short demo.

A new puzzle every day, the same for everyone. The day follows your device’s time zone. Solve it to keep your streak going and to join that day’s worldwide leaderboard. For more, choose Easy, Medium, or Hard and select New puzzle: practice is unlimited.

Each day’s board ranks everyone who solved that day’s puzzle by score, then time. Only your first result for the day counts. Hints and checks lower your score, so a clean solve ranks highest. Puzzles from the archive and practice puzzles are not ranked.

Koshi makes it for you: an adjective, an animal, and a number, such as “Quiet Crane 27”. You don’t need an account and there’s nothing to type. Names can’t be chosen or changed, and you keep yours on every board. Each device is its own player with its own name.

Today’s puzzle is ranked, so its board is hidden from screenshots, screen recordings, and mirroring to keep the leaderboard fair. Practice boards aren’t hidden, and Share makes a picture of your board once it’s solved.

Koshi Plus is a one-time in-app purchase, never a subscription. It opens every past daily in the archive, five inks for the board and your share cards, and Expert 12 × 14 boards. Today’s puzzle and Easy, Medium, and Hard practice stay free. The price for your country is shown in the app before you buy.

Open Settings and select Restore purchases in the Koshi Plus section. Use the same Apple Account, or on Android the same Google account, you bought it with, and make sure you’re connected to the internet. On Apple devices, Koshi Plus is also shared with your family through Family Sharing. Purchases don’t transfer between Apple devices and Android. If Plus is still missing, email us with your device and app version. Please don’t send payment card details or passwords.

On Apple devices, Koshi syncs your games, statistics, streak, rank, and settings through iCloud. Sign in to the same Apple Account with iCloud on each device. On Android, Koshi syncs the same through Google Play Games. You’re usually signed in automatically; otherwise, Settings shows Sign in to Google Play Games. Allow a moment for changes to arrive. Progress doesn’t sync between Apple devices and Android, and the daily reminder is set on each device.

Yes. Today’s puzzle and practice work without an internet connection, and your progress is saved on your device. Your result for Today’s puzzle is sent to the leaderboard when you’re back online. The leaderboard, purchases, restoring purchases, and syncing need a connection.

Yes. Email us your leaderboard name and a day you solved, with your score. See Delete your data in our privacy policy for the details.

Koshi is made for iPhone and iPad with iOS or iPadOS 26 or later, and for Android phones, tablets, and foldables with Android 14 or later. Larger screens can also play in landscape.

Apple handles App Store payments and refunds. Visit Apple’s Report a Problem page to view your purchases and request a refund. On Android, Google Play handles payments; see Google Play’s refund help.