In August 2026 I released EdgeNums, a number puzzle for Android, iOS, Windows and the browser. Every puzzle has exactly one solution and can be solved by logic alone, without guessing. It is free, has no ads and needs no account.
The screenshot below shows the homepage. It has the rules, a tutorial that solves one 5 by 5 puzzle move by move, and the links to the browser version and the stores.
How the puzzle works
The grid is N by N, from 4 up to 8. Each row and each column holds the numbers 1 to N-1 exactly once, plus one empty cell, which is shown in orange. The numbers around the grid are the edge numbers. Each one names the first number you see from that side. So it sits in the first cell of that row or column, or in the second one when the empty cell comes first. If you know Sudoku or Skyscrapers, the rules will look familiar.
Sizes and difficulty
4 by 4 is the size to get started. The sizes from 5 by 5 up to 8 by 8 come in three levels, easy, medium and hard. The harder the level, the fewer edge numbers are shown. The big grids start with a few numbers already placed, because the edge numbers alone are not enough there. Every puzzle is verified before you see it. It has exactly one solution and can be solved with the same logical steps the hints use. The Hint button does not reveal a cell from the solution. It shows the next logical step and explains in words why the value must go there.
Free and offline
EdgeNums is free. There are no ads, no in-app purchases and no account. The apps work offline, and the statistics with timer and best times stay on the device. The game is available in six languages. It runs in the browser without an installation, and the apps are in Google Play, the App Store and the Microsoft Store. EdgeNums is written in C# with .NET 10 and Avalonia 12, as one codebase for all four platforms.
Screenshots
That’s it.
If you have questions feel free to contact me.