Converting .mobi files to .htmlz format.
Converting Mobipocket eBooks directly to Zipped HTML eBooks (.mobi to .htmlz conversion) is not only possible, it's also quite straightforward.
Simply use one of several ebook management programs or conversion tools, such as Calibre or Hamster eBook Converter.
Alternatively, you will find numerous online conversion solutions capable of a .mobi to .htmlz conversion.