Getting Started

ClusterSum starts with three playable examples: complete a cluster, see why diagonals stay separate, and split a group that has grown too large. Replay the introduction from Settings → Replay First-Time Tutorial whenever you want.

Choose your mode

Journey begins with a small grid and progresses into larger boards and decorative blockers. Each level saves its current entries. After solving, inspect your completed board and choose Next Puzzle when you are ready.

Daily offers one puzzle for each local calendar date. Use the date arrows or calendar to browse today's puzzle and the previous 45 days. Completed dates are marked in the calendar. Daily stays on the selected date until you navigate elsewhere.

Get comfortable with the controls

• Tap a tile to cycle its number from 1 through 5.
• Drag vertically to choose a number; drag down to 0 to erase.
• Locked clues, hinted tiles, and decorative blockers cannot be edited.
• Select a tile to read its cluster count and status.
• Use Undo to reverse edits, or Reset Board to return to the clues and hinted values. A reset can be undone during the current session.

Hints, perfect solves, and coins

A hint places and locks a correct value. The first three hints per puzzle are free; additional hints cost 40 coins. Hints make the solve imperfect and clear undo history. A perfect solve uses no hints; Undo and Reset Board do not by themselves make it imperfect.

Coins come from Daily solve rewards, Daily Chest claims, Journey streak milestones, and optional StoreKit purchases. A hinted Journey solve can break a perfect streak; when offered, coin-based streak protection preserves that streak. Coin balance and progress are stored locally on the device.

Make the board feel like yours

Open Settings for colorful themes, the Vibration toggle, statistics by board size, and tutorial replay. ClusterSum supports VoiceOver tile values and adjustment actions, scrolling/stacked controls at accessibility text sizes, and reduced animation when the system's Reduce Motion setting is enabled.

Puzzle play works offline. In version 1.1 and later, optional iCloud sync shares progress between devices using the same iCloud account. Keep the app installed when updating to retain its local saves and coin balance.

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iCloud sync in version 1.1 and later

Enable Settings → iCloud Sync → Enable iCloud Sync on devices signed in to the same iCloud account. No separate ClusterSum account is needed. Enable it first on the device whose coin balance you want to keep: that device establishes the shared wallet. Other devices add their saved puzzles and Daily history without adding their old balances.

Journey progress, puzzle boards, Daily history, themes, and the shared coin wallet sync while ClusterSum is open. Haptics remain specific to each device. Play offline and use free hints as usual; with sync enabled, paid hints and streak protection require an iCloud connection. Earned rewards and purchases are reconciled without duplicate credits.

Use Sync Now to request an update and check the status and last-sync time. If both devices edited an unfinished puzzle independently, alternate saves are retained under Saved Board Versions. Finished boards and Daily completions are kept when saves merge. Local recovery copies are retained when sync is first enabled.

iPad orientation

Version 1.1 and later supports portrait and both landscape orientations. Rotate the iPad while playing; landscape places the controls beside the board. If rotation does not follow your device, check iPadOS Rotation Lock.