This app is free for today and is rated quite well ok. Smal-ish download size of 57MB.
Numberama 2 is the good old puzzle and probably the best time killer, that was popular in the universities and colleges at the 80's and 90's.
Info for haters: When you click new game, you see that numbers 1 2 3 4 5 6 7 8 9 11 12 13 14 15 16 17 18 19 (1 to 19 without 0's). If you remove 2 pairs (9+1, summ 10) and click rewrite, you see this: 1 2 3 4 5 6 7 8 1 12 13 14 15 16 17 18 and you will not see 9's again. It's not a problem it's original rules of the game. It's a part of a game or your strategy - choose right way to win.
The objective is to cross out neighbouring (vertically or continiously) pairs of digits to completely empty the screen. You can cross out the same numbers or the ones that give a total of 10.
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It only has 20 ratings with an average of 3.5