1. Start
Press a glowing endpoint. The cell lights up to confirm you are holding the head of the line.
The one line drawing puzzle.
Trace a single continuous line through a small grid. The longer the line, the more stars. Free on iOS and Android, plays offline.
Genre
What is a one line drawing puzzle?
A one line drawing puzzle is a puzzle where the player draws one continuous line — without lifting the pen and without crossing the line — through a grid or graph. Common goals include connecting two endpoints, visiting every cell, or maximising the line's length. The genre traces back to recreational mathematics (Euler's bridges of Königsberg, hamiltonian paths) and shows up in everything from primary-school worksheets to mobile puzzle apps.
monostroke is built around exactly this mechanic. Every level is a small grid; the player traces one stroke from a glowing endpoint, extending the line one cell at a time. The line cannot cross itself, jump walls, or skip cells. Star grading rewards path length: short but valid earns one star; the longest possible path — a hamiltonian path that touches every cell — earns three.
How it works
Drag, extend, complete.
2. Trace
Drag through neighbouring cells in any of the four cardinal directions. Your line cannot cross itself, jump walls, or skip cells. Drag back along your own line to retract.
3. Complete
Cover every required cell, then tap MARK COMPLETE. The longer the path, the more stars you earn — three stars requires a path that covers every cell.
Mechanics that unlock over time
- Walls — block movement between two adjacent cells.
- Checkpoints — mandatory cells the line must visit before completion.
- Ice — forces the line to slide in its direction of travel until it hits a wall or edge.
- Veils — hide adjacency. A veiled cell is invisible to neighbours, so the line can fold around it.
- Switches and gates — stepping a switch flips a paired gate open or closed.
- Portals — paired cells that teleport the line between them when entered.
- Mirrors — reflect the line across a marked axis. Both halves of the path stay synchronised.
Why monostroke
Built for the genre.
There are dozens of one-line-drawing apps in the stores. Most are hyper-casual: short levels, aggressive ads, daily-streak nag, paywall-locked content. monostroke takes a different shape.
Premium design
Calm dark palette, single ink colour, restrained UI. The interface gets out of the way so the puzzle stays in focus.
Cosmetic-only IAPs
The full puzzle set is free. In-app purchases buy themes and path skins. No level, mode, or mechanic is gated behind a purchase.
Progressive depth
New mechanics introduce one at a time over the first 60 levels. Three challenge worlds add focused twists. The Gauntlet is for players who want pressure.
FAQ
Common questions.
What is a one line drawing puzzle?
A one line drawing puzzle (also called a single-stroke puzzle) is a puzzle where the player draws one continuous line through a grid or graph without lifting the pen and without crossing the line. Common goals include connecting two endpoints, visiting every cell, or maximising the line's length. monostroke is built around this exact mechanic.
How do you play monostroke?
Press a glowing endpoint to start. Drag in any of the four cardinal directions — the line extends one cell at a time. Drag back along your line to retract. Submit when the line satisfies the level's rules; longer paths earn more stars.
What are the controls?
Single-finger tap-and-drag gestures. Drag back along the existing line to retract. No separate undo button — retracting is the undo. Portrait orientation, designed for one-thumb play.
Are there obstacles or special tiles?
Yes — mechanics unlock progressively in Endless mode. Walls, checkpoints, ice, veils, switches, portals, mirrors. Each adds a new constraint without changing the core single-stroke rule.
Is monostroke free?
Yes. The full puzzle set is free on iOS and Android. In-app purchases unlock cosmetic themes and path skins only.
Where can I download monostroke?
monostroke is available on the App Store and Google Play. Free on both.
Get monostroke
Free on iOS and Android.
No account. Plays offline. The full puzzle set is free.