Suguru is a Japanese puzzle game also known as Number Blocks and Tectonics. It is great for all ages.
64000 grids ranging from 5x5 up to 9x9.
The goal is simple; fill the grid with numbers so that each number appears exactly once in each region and so that neighboring cells do not contain the same number.
Easy, and regular difficulties with hints for all difficulty levels. You will never be left without a hint if you need one.
Smaller grids are great for younger players or if you just want a quick game. Larger grids will provide a challenge to even the best puzzle solvers.
Grids can be zoomed in and out using a spread and pinch motion to easily complete large grids even on smaller devices.