Stelline: Star Logic Puzzles

Every board is generated on your iPhone and proven to have exactly one solution. Tap, dot, deduce. Hints teach each step. No ads, no account, nothing leaves your phone.

Stelline is a calm Star Battle-style logic game for people who solve by reasoning, not by trial and error. Every board is generated on your iPhone, verified to have exactly one solution, and graded by the same deduction engine that powers its hints. No ads, no account, and nothing ever leaves your phone.

THE RULES Place one queen in every row, every column and every coloured region, and never let two queens touch, not even at a corner. When that feels easy, switch to 2-star mode: two stars in every row, column and region on boards up to 11×11, still never touching.

UNLIMITED BOARDS, EACH ONE PROVEN

• Boards are built on your device, so there is no pack to run out of and nothing to download.
• Every board is checked by an exact solver before you see it: exactly one solution, always.
• 1-queen boards from 6×6 to 11×11; 2-star boards from 9×9 to 11×11.
• Compete: Today's board for everyone, daily leaderboards, a numbered archive of past boards.

DIFFICULTY GRADED BY DEDUCTION

• A deduction engine with seventeen techniques solves each board the way a person would, from finished rows and neighbour dots to line locks, exclusion, counting arguments, X-wings, squeezes and fish.
• Easy, Medium and Hard boards need direct deductions only, in both modes.
• Expert is labelled honestly: it needs what-if reasoning, one level and never nested in 1-queen mode; a few 2-star boards go beyond what the hints can explain.
• The difficulty badge sits next to the timer.

HINTS THAT TEACH

• Hint first shows two counters, misplaced queens and misplaced dots, without saying where they are. Zero and zero means your reasoning holds so far.
• Show me where walks you through one logical step at a time: it highlights the row, column or region behind the next deduction, then the cells, names the technique with a one-line explanation, and applies the step only when you tap Do it.
• Wandered off the solution? The same ladder narrows the mistake down to the region, then the exact marks, and clears them at your request.
• Hints are unlimited, with no cooldown. Solve with no hints and no conflicts to earn the Flawless badge.

CONTROLS BUILT FOR CLEAN SOLVING

• Tap a cell to cycle it: empty, dot, queen or star.
• Drag across cells to dot them; start on a dot you placed to erase instead.
• A placed queen or star dots its eight neighbours for you; completed rows, columns and regions can dot themselves too. Both are optional.
• Auto-check stripes queens or stars that touch or exceed a row, column or region. Turn it off for a purist solve.
• Undo, redo and clear, with the history saved alongside your game.
• A timer you can hide. No lives, no streaks, no pressure.
• Your game saves itself after every move. Leave, come back, tap Continue.

MADE FOR EVERY PLAYER

• An original pastel palette with a named colour for every region, or the Classic black-and-white look with heavy region borders for players who learned on paper.
• Colour-blind mode: high-contrast colours, a distinct fill pattern for every region and thicker borders.
• Light, dark or system appearance. Choose a crown or a star as your piece, a dot or an X as your mark.
• Full VoiceOver support: every cell announces its state, region colour, row and column, and hints are read aloud. Dynamic Type and Reduce Motion are respected throughout.
• Haptic feedback you can switch off.

PRIVATE BY DESIGN Stelline has no account, no ads and no analytics. Your boards, settings and progress stay on your phone; nothing is collected. The only online feature is the optional Game Center leaderboard, run by Apple and off by default. Play on a plane, underground or anywhere else.

FROM ONE DEVELOPER Stelline (little stars) is written from scratch in Swift for iPhone, including its own generator, solver and deduction engine. It is a small app that tries to do one thing carefully: give you a fair puzzle, every time. A six-slide How to play guide covers the rules and the controls in a minute. After that, the board is yours.