Each Kindle device and app has its own unique rendering engines for books. I've noticed that there are differences in the way a book is rendered between my Kindle Touch, Kindle Fire, and Kindle app for iPad. The differences are usually much more subtle than the one described here though. My guess is that the author/publisher hard coded some font size information into the book and the Kindle non-touch and Kindle for Android app are displaying it differently according to the way their rendering engines work. On the other hand, if the book was a KF8 book, Amazon seems to have implemented KF8 to varying degrees on Kindle apps depending on the platform.