PopStar with Undo

Highly addictive game. Once you start, you cannot stop.
There are two modes.
Game rule
Classic:
- Tap two or more blocks, which are same color
- No time limit, once you meet target you can promote to next level
Endless:
- Tap two or more blocks, which are same color
- Tap the blocks as more and fast as you can
- The more block you tap once, the more time will be added
- When level up the time drain will be faster
- Once time up it will game over
Score rule:
Score = block x block x 5
Bonus rule of Classic mode:
bonus = 2000 - block x block x 20
Features:
- Undo Button
- 9 different color blocks, you can choose random color or fixed color