Divi. is a surprisingly addictive and fun app that will help students gain speed and fluency at factors, multiples, and divisibility rules to help them improve their skills with equivalent fractions, simplifying fractions, and finding common denominators.
Times Table Galaxy is a fun and effective system for practicing multiplication facts in timed and competitive settings. The app supports both development of skill at skip counting and improvement in speed and memorization of multiplication combinations 2 x 2 to 12 x 12.
Reasonably priced, Mathly Hollows nicely combines education and entertainment. Despite missing a few key features, it is a pleasure to play. This app may be best suited for kids in first grade and older.