eCub is a cross-platform tool for creating EPUB and MobiPocket books. EPUB is become a popular e-book standard and is open and free for all to implement. EPUB files can be read by MobiPocket, Adobe Digital Editions, FBReader, Stanza, the Sony Reader, and many other readers and applications. MobiPocket books can be read on desktop platforms, mobile platforms and the Amazon Kindle e-book reader.