I wrote this app to help my (then 9) year old daughter pass the maths part of 11+ exam (A secondary school entrance exam here in the UK). AFAICS, it's functionally great and poses the kind of questions you actually get asked on the test. Random questions on a random test each time you start it up. I put it up on the play store (free with unobtrusive ads) in September, since when, as of right now, it has had 49 downloads.
I'm interested to find out how you think it could be improved or modified to be more attractive. I know it's visually dull, but I just have a brain melt on this every time I try to address it, and can't see my way to making it successful.