I'm working with the app producer Thinkout, who's just released an app (Number Bonds by Thinkout) for enhancing children's learning and understanding numbers. Since you seem to be writing on learning and technology, we'd be happy to get a review from you.
In the work with the app, a book was written as well, to explain how it differs from other edutainment apps out there. Most of the it can't be seen on the screen, but is "hidden in code". If you're interested, I could send you a book or you can download it at Thinkout's website: www.thinkout.se/book. If you'd like me to send you the book, please provide me your address.
The company, Thinkout, was founded by Mr Rolf Skoglund, former VP at Microsoft, and the idea of the app is based on research from Professor Diana Laurillard, University of London.