One Line — One Stroke Puzzle

One Line is a clean, calming one-stroke puzzle.

Trace a single continuous line that crosses every edge of the figure exactly once — without lifting your finger and without retracing a line you've already drawn. It's the classic "draw it in one stroke" puzzle you knew as a kid, rebuilt as a relaxing, ad-light pocket game.

★ FEATURES

• Hundreds of solvable puzzles. Every level is generated to guarantee a one-stroke solution exists — no impossible boards, ever.
• Dead-simple controls — just drag your finger from dot to dot.
• A difficulty curve that actually grows: a few edges at first, branching networks later.
• Unlimited Undo and Restart — experiment freely with no penalty.
• Stuck? Tap Hint to reveal the next stroke of the path (optional rewarded ad).
• Glowing line trails, a soft tactile feel, and gentle sound — both sound and haptics can be toggled.
• Works fully offline. No login, no account, no nag screens.

★ HOW TO PLAY

1. Touch any dot to start your line.
2. Drag to a connected dot to draw that edge.
3. Drag back to undo the last edge any time.
4. Cover every edge exactly once to clear the level.

★ WHY YOU'LL LOVE IT

• Minimal, glowing visuals — dots and a single bright line, nothing else.
• Plays great in short bursts (one level in under a minute) or long focused sessions.
• Tiny app size with smooth animations.
• A true brain workout: planning your route is the whole game.

★ ABOUT DIFFICULTY

Each level is built by walking a path across a grid, so the puzzle you see is always something that can be drawn in one stroke. Early levels teach the idea in a handful of moves; later levels open up into branching networks where choosing the right turn matters.

Hint is there for the moments you've boxed yourself in — but with a little planning, you'll learn to read the whole path before you start.

★ PRIVACY

One Line doesn't collect any personal information. The only third party is Google AdMob, which serves the ads that keep the game free. EEA/UK users see the standard consent dialog on first launch. All your progress is stored only on your device.