Pairs of bubbles float on the screen and your goal is to pop each pair. For example, one bubble says "7" and another says "3+4". Simply touch one bubble and then the other to pop them both. At any time, you can choose different operators: addition, subtraction, multiplication and division.
Once you've popped all pairs on a level, you see your time for that level and can move on to the next level, or keep practicing that level.