[Android] Kindle Android app, page flip, and calibre

Hello everyone

As I (sadly) don't have a dedicated book reader device, I use my android tablet for reading. Most of the time the Amazon Kindle Android app is what I use, and with the new option to move downloaded books to "external SD card", page flip and whispersync I'm quite happy with it.
However, I'm wondering if I could somehow sync my non-amazon ebooks with my android Kindle app. I can save them to the Kindle folder on "Internal SD card", but this way I won't get page flip nor whispersync. Sending my files by email also won't give me these features. And, being able to have my books on "external SD" would be a great space saver.

Thanks