Sharpen your mind with a connect-the-block-style one-line brain training puzzle game.
A simple but addictive one-line puzzle game that’s completely free to play.

Your brain becomes more active the more you play.
During your commute, before you sleep… enjoy downtime with brain training.

The rules are extremely simple.
Just fill in all of the blocks using only one line.

Use hints for puzzles that are too hard to solve.
Hints are also free, of course.

4 levels of difficulty.
A whopping 2,000 puzzles.
Don’t get too cozy—the puzzles get harder as you go along.

One-line puzzles are mathematical problems with origins in the early 18th century. First posed in Königsberg, the original puzzle revolved around the town’s Pregel River.
Mathematical thinking is said to increase work efficiency and prevent aging.
Whether math is your bane or your forte, be sure to give this game a try.
You’re sure to get hooked on these puzzles!

What's New

Version 3.0.2

Thank you for always using it.
We have carried out the following update.

* Improve performance
* Minor modification

Please continue your favors toward "Fill - one-line puzzle game" in the future.

Ratings and Reviews

4.6 out of 5

6.2K Ratings

6.2K Ratings

Too many ads!


This fun addictive game has plenty of gameplay value and thousands of puzzle to solve. You find yourself solving them quickly, several in a row in no time flat. Unfortunately, this momentum is completely broken by the full screen, make you play a demo of a game and cant immediately click out of it advertisement. I understand that you need adverts to generate income, but I have to see the same ad after every 2-4 levels. If you pause to answer a text, another ad. Anytime you start the game, another ad. Finish a block of 100 puzzles and you are rewarded with 2 of the same ad in a row! It’s a fun game when I get to play it, but the ad pops up so frequently that it feels like I am playing two games whether I want to or not. One last dirty trick on those ads: when you have waited the entire necessary amount of time to click the ‘x’ to get out, you have to find it because it doesn’t appear in the same place all the time.

This game has had no problems


OMG you guys! You need this game I promise if you like figuring out puzzles you will love just like I do!! This game is ADDICTING and fun! I never write a review. But I decided that this game is sooo good I’d just have to let y’all know how fun and how good of a game it is. You will never regret having this game!!

REMEMBER: you will only like it if you like puzzles so I do not recommend it if you like other kind of games! So don’t go blaming on me if you don’t like it I told you there’s a chance that you will not like it if you don’t like puzzles! PUZZLES!!

New update


I love this game very much. The puzzles are really easy yet difficult to solve. The only issue I have, is with the newest update. Before, after completing a level, a small little box will appear in the middle of the screen. Now, the box is the entire screen that lags a lot and the "next level" button is at the bottom which is very uncomfortable. It makes me want to stop playing compared to before. Please bring back the old completion box. I'm sure it'll help your app's popularity.


MagicAnt LLC
86.6 MB
Requires iOS 8.0 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© MagicAnt,Inc
In-App Purchases
  1. Remove Ads $2.99
  2. 10 Hints $0.99
  3. 55 Hints $4.99


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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