Some portable multimedia players and smartphones include a text viewer, e.g. several Cowon players, including the Cowon D2 and the iAUDIO U3 and Mobipocket Reader for Symbian OS and Windows Mobile mobile phones and devices. Adobe Reader mobile also turns Windows Mobile devices (for example, Samsung Omnia) into suitable e-Book viewers. Apple's iPhone, iPad and iPod Touch are also acquiring status as e-book readers through the Lexcycle Stanza and eReader apps. A recent Windows Mobile phone from HTC, the HD2 model, has a larger screen with higher resolution than the iPhone, and is also becoming a popular ebook platform. WordPlayer or FBReader turns Android phones into e-book readers. PalmOS based devices and smartphones are also usable for reading books. PalmOS supports PalmDoc, iSilo, Mobipocket reader, PDF, HTML conversion, text format, Handstory, TealDoc among many other software titles, in addition to on-the-device word processing.
There are also mobile devices capable of wordprocessing. Conversely, fully functional tablet notebooks (with screens that turn 180 degrees and lie with the back to the keyboard) and subnotebooks are used as e-book-readers.
Source from wikipedia.org