Trace every line exactly once without lifting your pen. OneTrail builds each board on your device and checks that it can be solved before it ever reaches the screen — so you'll never run into a board that can't be finished.
From a set Journey to a Daily Puzzle the whole world shares, and an Endless mode that never runs out of boards.
8 worlds × 30 boards: grid, diagonal, triangle, radial, mandala, spiderweb. Seeds are fixed, so World 4 Stage 12 is the same board on every device.
The date alone decides the board, so everyone solves the same one. Shape and difficulty change by weekday, and a streak calendar tracks your run.
Pick board shape, size, difficulty, and whether you must end where you started — then get a fresh board every time.
How many boards can you clear in one minute? The more you solve, the bigger they get.
The envelope, the House of Santa Claus, the Seven Bridges of Königsberg, the Star of David, a snowflake, a gear — each hand-designed and verified.
It calculates whether the remaining lines can still be completed, and if you're already stuck, rewinds to the last point that was still alive.
Difficulty isn't measured by line count. It's measured by the chance that someone drawing at random gets it on the first try. The more fork traps a board has, the lower that number drops — and that's exactly why it feels hard.
Fully offline — it runs start to finish in airplane mode. No account, no login;
every record stays on this device. No location, camera, microphone, or storage permissions.
Ads never lock the game. Hints are a bonus, and when no ad is available you simply get the hint.
Only boards verified solvable — no dead ends built in.
📲 Get it on Google Play