[Sabardeyn]

Ok, I'm only half remembering things here because the situation did not, and could not, apply to me - I convert everything to EPUBs.

But isn't there a problem with one of the reader apps because it doesn't declare to the Android OS that it accepts a certain ebook format? As I recall it will automatically load one format (MOBI?) but totally ignores the second format (AZW?). It does work with the second format - but you have to manually load the ebook. Clicking on the second file format won't automatically launch the reader and load the book.

Again, I might be mistaken which reader app and formats this affects, but it is a known error for Android devices.