As a UI developer with about 5 years of experience, that seems about right to me. I think I could have written that app given about 8 months. Heck, I suspect that the page turning animation was a relatively small part of the development.

I don't consider myself a fantastic developer either. I'd be suspicious of any developer with a few years experience who couldn't write an application like that given the right amount of time and motivation.

This isn't to belittle your comment, just that I'm thinking to myself "yeah, that sound correct".