The ePub format is an open standard for e-books created by the IDPF. The format can be read by all major current eReaders (Nook, Sony, Kobo,...) with the exception of the Amazon Kindle's eReaders.
The Mobipocket (Mobi) format is a format based on the Open eBook standard and is mostly suitable for Amazon Kindle's eReaders.
The table below summarizes the eBook format compatible with your favorite eReader:
|eReader||ePub support||Mobi support|
|Amazon Kindle 1, 2, DX||No||Yes|
|Apple iPad, iPhone, iPod||Yes||No|
|Barnes & Noble Nook, Nook color||Yes||No|
|Sony Reader (Pocket, Daily, Touch)||Yes||No|