The Kindle for iOS app would be nearly perfect IMO if they would FINALLY add very small margins (on iPhones) and the ability to add our own fonts. At the very least they should add the ability for it to display embedded fonts, an ability already available on many eInk Kindles and I think on Kindle Fires as well.

Even as is, it is still my go to app for reading because of the Amazon ecosystem that allows the best syncing between devices, computers, etc.