Suguru Nature is a great logic puzzle with two simple rules.
The cells in each puzzle grid are divided into groups, and each group contains the numbers from 1 to N, where N is the number of cells in the group. Thus, a group containing 5 cells will contain numbers from 1 to 5. The second rule is that no two adjacent cells, including diagonal, can contain the same number.
Suguru / tectonics is a really fun and intuitive puzzle game that employs logic in a similar way to Sudoku, and this app is functional and serves as a good introduction to this kind of puzzle. While this is usually listed at €9.99, I got this for Black Friday in 2020 for only €0.99, when I was playing on the Nintendo Switch Lite.
The game has 90 puzzles, broken into three difficulty levels: Easy/Medium/Hard, and I have to say the hard ones are not that hard, but annoying, as they are usually multi-solution puzzles that might fret you back and forth. A good thing is the minimal UI with beautiful backgrounds, and I’d also praise the soundtrack, if it wasn’t so damn repetitive. Otherwise, it’s a fun little game and if you get the chance of getting it for less than a soda, it’s definitely worth it. Only big drawback? It’s a Switch exclusive. Four joysticks.