Fill one-line puzzle game

Fill one-line puzzle game asks you to trace a single continuous path through every block on a grid without lifting your finger or retracing a step. It is a clean execution of a concept rooted in 18th-century graph theory, and with 2,000 puzzles spread across four difficulty tiers, it offers genuine staying power. The free price tag and free hints lower the barrier considerably, though the app clocks in at 140 MB, which feels heavy for what is essentially a grid-drawing game.

What It Gets Right

The core loop is immediately legible. You tap a starting block and drag through the grid, and the single rule, cover every block in one unbroken line, never needs explaining twice. The four difficulty levels create a real progression curve rather than a cosmetic one, and the availability of free hints means frustration rarely turns into a dead end. After eight years of updates, the latest being November 2024, the puzzle set feels well maintained rather than abandoned.

Where It Feels Its Age

At 140 MB the download is disproportionate to the content on screen. The app launched in 2016 and while it has been updated, the visual design reflects that era, functional but plain. There are in-app purchases present, and without hands-on spending data it is hard to know how aggressively they surface, which is worth noting for anyone sensitive to monetization interruptions in a puzzle flow.

Who Should Download It

Commuters and casual puzzle fans who want a low-friction brain exercise will find 2,000 puzzles more than enough to fill idle minutes. It suits people who enjoy Hamiltonian path-style logic but do not want the overhead of a complex game system. The 40,000-rating base with a 4.64 average suggests a loyal audience, making it a reasonable recommendation for anyone who likes one-more-puzzle sessions before bed.