Ell Tee is the creator of numDance, which is a point scoring puzzle app game. It's tough to explain.
  
1.  Only 1's or 2's can be tapped.
2.  They can be tapped if and only if there are 2 identical numbers adjacent to it.
3.  Two 2's will merge to form a single 3 in the space between them.

The first tap will automatically lead to a massive chain reaction. Coming up with a strategy is tougher than I thought.
My high score is 1164 and my highest tile is 8.
numDance definitely has an addictive element because you can play one game in about 5 minutes.
If you manage to get a 9 tile, take a screen shot and post it in the comments section.
https://itunes.apple.com/de/app/numdance/id1134557051"mt=8

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