# Kerfline: One-Tap Gravity Flip — Hardest One-Tap Arcade Levels > Hardest One-Tap Arcade Levels (iPhone/iPad app by Mohammad Nabulsi.) - Source: https://appshunter.io/ios/app/kerfline-one-tap-gravity-flip/id6800692981 (this page in markdown: same URL + `.md`) - Developer: [Mohammad Nabulsi](https://appshunter.io/developer/6787727908) - Category: Games, Entertainment, Action, Casual - Price: Free - Age rating: 4+ - Requires: iOS 18.0 · 97 MB - Languages: American English - Released: 2026-09-21 - Data updated: 2026-10-10 ## What is Kerfline? A dot. A wire. One tap. The wire has two sides. The dot rides one of them. Tap, and gravity flips it to the other. That's the whole rulebook — everything else is what the wire does to you. Wires curve. They spiral. They split, and the side of the wire your dot is on decides which prong it takes. Spikes wait in your path with just enough warning to dodge them, if your timing's honest. Gaps open under the wire and the dot has to cross on nothing but physics. Nothing here is random. Every hazard is exactly where it was the last time you died, so every death is yours to own. One touch and it's over. Restart is instant — no loading screen, no "tap to retry." 70+ hand-built levels get harder in ways that are fair and never in ways that are cheap. Some of them are the hardest one-tap levels you'll play this year. A few will take you a long time. That's on purpose. Every level tracks your deaths and shows you the percentage of players who've actually beaten it — sometimes it's a humbling number. A separate timer clocks your best runs, but the leaderboard that matters ranks fewest deaths, because two players on the same route tie on time and only one of them died less. Clear a level and you can share it — your death count, your completion percentage, one tap. Cosmetic trails and skins are earned, never bought: clear the hardest levels, finish one without dying, or clear the whole set. Proof, not decoration — and not one of them changes what a level asks of you. Kerfline is free with ads. Now and then, after a death, a short video ad appears — most of the time you can choose to skip it. Nothing in the game is for sale — there are no in-app purchases, and every cosmetic is earned. One wire. One tap. Plenty of ways to lose an afternoon. ## Is Kerfline safe? Not enough ratings yet to assess Kerfline. ## Is Kerfline legit? Kerfline: One-Tap Gravity Flip has limited verification signals. The AppsHunter Legitimacy Score for Kerfline is 58 out of 100 points across 7 verification signals from App Store and developer data. ## Version history (last 5 releases) ### 1.0.4 — 2026-10-01 20 new levels, with more to come. Forks now send the dot down the prong on the side it is on, so a fork goes the way you expect. Still one tap. Still instant restart. ### 1.0.3 — 2026-09-28 Bug fixes and improvements. - The name field now reminds you that your leaderboard name is public. - Clearer privacy summary in Settings. ### 1.0.2 — 2026-09-25 Bug fixes and improvements. ### 1.0.1 — 2026-09-22 New: Gilt and Rosewood cosmetic trails, unlocked by watching a short video. Added a light theme alongside dark. ### 1.0.0 — 2026-09-22 No release notes. ## Apps similar to Kerfline | App | Rating | Price | Category | | --- | --- | --- | --- | | [Freelance Tycoon: Agency Sim](https://appshunter.io/ios/app/freelance-tycoon-agency-sim/id6759949417) | — | Free | Games | | [Defender II](https://appshunter.io/ios/app/defender-ii/id550081851) | 4.2 (1,093) | Free | Games | | [East Trade Tycoon](https://appshunter.io/ios/app/east-trade-tycoon/id1609590125) | 4.2 (115) | Free | Games | | [Business Game - Life Simulator](https://appshunter.io/ios/app/business-game-life-simulator/id1627892457) | 4.4 (419) | Free | Games | | [Idle Code Tycoon](https://appshunter.io/ios/app/idle-code-tycoon/id6754207431) | 4.8 (335) | Free | Games | | [Good Roommates Life Simulator](https://appshunter.io/ios/app/good-roommates-life-simulator/id6744338524) | 4.6 (1,845) | Free | Games | ## More apps by Mohammad Nabulsi - [MeloTouch: Sensory Fidget](https://appshunter.io/ios/app/melotouch-sensory-fidget/id6787727906) All apps by Mohammad Nabulsi: https://appshunter.io/developer/6787727908 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-10.*