Keepsum

Screenshots

App Info

A logic puzzle: on a board full of numbers, choose which numbers to keep and which to erase so that every row and column adds up to its clue.

• Every puzzle has exactly one answer, and every puzzle can be solved step by step without guessing.
• There are no lives. A mistake never ends the puzzle, and hints and undo are unlimited. Only Rush has a time limit.
• No sign-up, no login. The first time you open the app, a short guide teaches the rules on a small board.
• The game works offline. The internet is used only for the ad at the bottom and for usage statistics.
• The language follows your device. English, Korean, Japanese and Chinese (Simplified and Traditional) are supported, and you can also pick one in Settings.

1. Rules

• The numbers above the board are the clues for the columns; the numbers on the left are the clues for the rows.
• In each cell, you either keep the number (circle it) or erase it (it fades to a dot).
• In every row and column, the numbers you keep must add up to the clue.
• When every row and column adds up, the puzzle is solved.

What the clues show

• When every cell in a line is decided and the sum matches, its clue gets a check.
• When every cell is decided but the sum is wrong, the clue's outline turns hatched, so you can tell by shape as well as color.
• When the numbers you kept already make the clue but some cells in the line are still open, the clue gets a yellow outline. Tap that clue to erase the rest of the line at once (whichever tool is selected).

2. Controls

• Pick a tool with Erase and Keep at the bottom center, then tap a cell.
  • Keep: circles the number.
  • Erase: the number shrinks and fades to a dot.
  • Tapping a decided cell again with the same tool clears it. Tapping an erased cell with Keep turns it into a kept cell right away.
• Kept cells don't change with the Erase tool. The circle pops slightly and you hear a click. To release a kept cell, tap it again with Keep.
• Drag to paint: press and drag to paint every cell you pass with the same tool, along the line (row or column) you first moved in. Only cells that were in the same state as the first cell change. One drag is undone with a single undo.
• While you hold a cell, its row and column and their two clues light up (Row and column guide in Settings, on at first).

The buttons at the bottom (Classic and Daily):

Hints

• Step 1 highlights the line to look at (for example 'Look at this row.'). When two lines have to be read together, both light up. Tap Why? to see step 2.
• Step 2 shows the cell to decide and why (for example 'Without 9, the other numbers can't reach the clue 31. Keep this 9.'). A tag names the reasoning used (Too big, Needs every number, Can't do without, Doesn't fit, In every combination, Two lines together). Tap Apply to decide that cell.
• If a cell doesn't match the answer, the hint points to it first (tag Fix a mistake). If there are several, the earliest one comes first.
• With no wrong cells, the hint shows the easiest step you can take now.

The Restart (↻) button on the right of the top bar:

Next to it, the Quick settings button opens a sheet for changing sounds, vibration, effects and board settings without leaving the game. Tap above the sheet or drag it down to close it. Exit is at the far right.

3. Modes

Classic — no timer

• On the home screen, choose a board size (5×5 · 6×6 · 7×7 · 8×8 · 9×9) with the tabs on top of the Classic card and tap Play. If you have a puzzle in progress, the button says Continue. You can also swipe the board preview to change sizes, and tap the preview to start right away.
• At first only 5×5 is open. Solve a set number of puzzles on your largest size to unlock the next one (3 on 5×5, 4 on 6×6, 5 on 7×7, 5 on 8×8). The line under the preview shows how many are left to the next size.
• The more puzzles you solve on a size, the harder its puzzles get (one step every three puzzles; once you reach the hardest step, the two hardest steps take turns). The dots next to the size in the game show the puzzle's difficulty.
• The board preview on the card shows only your progress on the puzzle in progress (circles, erased cells, checks). Numbers and clues are hidden behind '?'.
• The time isn't shown while you play. The result shows how long you took, and your best time is kept for each size.
• Puzzles in progress are saved automatically. Leave, or even restart the app, and you continue where you left off on each size, undo history included. If you leave without deciding any cell, the puzzle starts fresh next time (time and hints too).

Daily — today's puzzle

• One 7×7 puzzle each day. Everyone in the world gets the same puzzle on the same day (by your device's date). A new Daily opens at midnight on your device's clock.
• There's no time limit; the time you've spent is shown at the top. You can use hints, and the number you used is kept in the result.
• Within the day, you can leave and come back. Restart this puzzle keeps counting your time and hints.
• Your streak grows with each day you solve the Daily and breaks if you miss a day. With no lives and unlimited hints, there is no failing.
• Send your result with Share on the result screen. For example:

Keepsum Daily #12 ✅ 6:41
Hints 1
🔥 5-day streak

#12 is the Daily number, followed by your time. The second line shows the hints you used and the third your streak (shown from two days on). Launch day is #1 and the number goes up by one each day, so the same number means the same puzzle. The result screen also shows the time until the next Daily.

Rush — solve against the clock

• A 3 · 2 · 1 countdown comes first. Then solve 5×5 puzzles one after another before time runs out.
• You start with 3 minutes and get 30 more seconds for each puzzle you solve. Every two puzzles, the next ones get a little harder.
• There are no hints or undo. Show mistakes in Settings isn't used in Rush (Show current sums and Erase the rest automatically follow your settings).
• If you leave the app, the clock stops and the board is hidden. Come back and tap Resume to carry on. If the countdown was running, it starts again from 3.
• In the last 10 seconds you hear the clock tick. When time is up, you see how many puzzles you solved, your best and your number of runs.

4. Records

Open them with the trophy button at the top right of the home screen. It shows how many puzzles you've solved.

• At the top: the puzzles you solved in Classic and Daily
• Classic: puzzles solved, best time and average time for each size. Of the locked sizes, only the next one shows what unlocks it, with a bar.
• Daily: streak, longest streak and days solved. The calendar marks the days you solved with a check.
• Rush: best (puzzles solved) and runs

5. Settings

Open them with the gear at the top right of the home screen. During a game, the Quick settings button in the top bar changes sounds, vibration, effects and board settings right away.

6. Ads and your records

• A single banner ad sits at the very bottom of the screen. While you play Rush and during the first-run guide, the ad is removed and only its space is kept.
• Your records and settings are stored on your device. If your device's Google backup is on, they are included in the backup, so you can carry on after switching devices. Uninstalling the app deletes the records on the device.
• For details, see the Privacy Policy.

7. Contact