It can read directly from inside ZIP files, and supports BMP, GIF, PNG and JPG images. It offers many customization options including: Portrait and Landscape display, Choice of font type, color and size, etc.... It Also has a resizable/skinnable User Interface.
There is also a µBookLite version. µBookLite for Palm OS (3.5+), Pocket PC / Mobile PC (Windows CE 3.0+) (soon for Smartphone) is a simple and lean, yet powerful ebook reader that can read PDB and PRC (not secure) ebook (in HTML, TXT or PML format).
For the Palm the font packs are downloadable separately.
For more details see http://www.gowerpoint.com/