Math in Motion for kids (com.ditiva.MathInMotion) on Google Play
"Math in Motion" is a FREE App with which kids have fun while practicing math.The App includes 3 levels of difficulty to suit the needs of each child. It starts with addition and, as you progress, includes subtraction, multiplication and division. It will also increase the speed of the bubbles and will reduce the time allowed to respond.The best score is recorded, so you may see their progress.