slide and fit puzzles into center square

features
1: slide and fit puzzles into simple 3x3 4x4 5x5 center square.
2: all puzzles are numbered
3: one puzzle is allowed to move at one time.

your brain will be trained into clever brain.

difficulties consist of four categories (beginner,intermediate,expert,custom)

beginner difficulty is 3x3 and slide and fit puzzles into center square.
intermediate difficulty is 4x4 and slide and fit puzzles into center square.
expert difficulty is 5x5 and slide and fit puzzles into center square.
custom difficulty is 3x3, 4x4, or 5x5 for your selection with camera.

each difficulty has 12 levels currently and all 12*3=36 levels totally.