Please take a look at the NumberBonds by Thinkout app and, if you like it, VOTE for the App.
You can vote once a day, every day till March 21.
Winners will be announced on March 30.
NumberBonds was originally developed in the project on Adaptive games for learners with numeracy difficulties by Diana Laurillard and Hassan Baajour. It attracted investment funding from Thinkout.se in Stockholm to develop it as an app: 'NumberBonds by Thinkout'.
See also Butterworth, B., Varma, S., & Laurillard, D. (2011). Dyscalculia: From Brain to Education. Science, 332, 1049-1053.