Amazon not only uses DRM but it uses a non-standard ebook format and its hardware does not support vanilla ePub (out of the box, you can download third party vi

Amazon not only uses DRM but it uses a non-standard ebook format and its hardware does not support vanilla ePub (out of the box, you can download third party viewers to the Fire devices Amazon uses the MobiPocket format, which was the standard eBook format before ebooks became popular. The Topaz and Azul formats are only used for books which are converted by publishers to ebook by scanning them and OCR'ing the text. These formats appear to be based on the PDF format but the DRM mechanism is non-standard. Amazon Kindle hardware does support ePub. The software does not. That is a major difference--if the hardware did nto support ePub, it would not be meaningfully possible to add support in via hardware.