Abacus Number Sense app for iPhone and iPad

Abacus is a visual, interactive experience for building student confidence in number sense and basic operations. No multiple choice or fill in the blank. Deeply interactive sequences and animations give students space to explore math concepts for themselves and build intuitive familiarity with foundational concepts such as count, place value, adding, and subtracting.

This is an early version of Abacus, and we are releasing updates frequently. We appreciate your feedback and will take it into account. And theres much more on the way!