+ -sometimes0 (+ - sometimes 0) is a calculated game.
By calculation result +, -, we will continue to answer by tapping 0.
Lets take a quick answer.
Also I is compatible with Game Center.
As you clear the QUEST opens new STAGE.
STAGE until 1-9! Will become more and more high mental arithmetic degree of difficulty.
If it is not master of mental arithmetic to the last STAGE will not Tadoritsuka.
Wonder if you can go to where?