99 grids puzzle is a simple but addicting app, don't doubt,it's free! 

Its the perfect little game to pick up and play when you have a spare moment.

The goal is to uncover all the grids while avoiding the mines.

The rules are simple: A number indicates the total number of mines on the 8 grids around it. Long pressing to mark as grid as being a mine.

FEATURES:
-Challenge the best with time mode
-Single tap or long press
-3 difficulty levels
-Flag tiles with long press
-Sounds and music
-Achievement
-Auto placement of cards to goal cells

DIFFICULTIES:

- Beginner 6x9 with 8 mines
- Intermediate 8x11 with 12 mines
- Expert 10x14 with 24 mines