ClusterSum is a number-logic puzzle for iPhone and iPad. Fill the board so every connected group of equal numbers contains exactly as many tiles as its number. Three connected 3s make a complete cluster; diagonals stay separate.
Daily puzzles and Journey progression
Play a fresh Daily puzzle, browse the recent archive with the calendar and date arrows, or follow Journey into larger boards and decorative blockers. Completed Journey boards stay visible until you choose Next Puzzle.
Continue on iPhone and iPad
The version 1.1.0 update adds optional iCloud sync. Enable it on devices using the same iCloud account to share saved puzzles, Daily history, themes, and coins. The first device sets the starting coin balance; other devices contribute their progress without adding their old balances. This feature becomes available on the App Store after Apple approves the update.
Puzzle play stays available offline. With sync enabled, spending coins requires an iCloud connection. Device-specific board versions are retained when independent edits need to be reconciled.
Room to experiment
Tap to cycle numbers or drag vertically to choose a value. Undo an edit or undo a Reset Board while you work out how the groups fit. The first three hints per puzzle are free; additional hints and Journey streak protection use coins.
Make it your own
- iPad portrait and landscape play in version 1.1 and later
- Colorful themes and optional haptics
- Playable introduction to the rules
- VoiceOver tile controls
- Larger-text layouts and Reduce Motion support
- Offline puzzle play and local saved progress
ClusterSum is free to download for iPhone and iPad, with optional in-app coin purchases. No separate ClusterSum account is required. Progress saves locally, with optional iCloud sync in version 1.1 and later.
Download ClusterSum on the App Store