I just got a Motorola Backflip Android phone and am in love with iReader.
It reads secure eReader (.pdb) and Mobipocket secure (.prc). The Mobipocket is a hack - you put in the PIN as opposed to using the actual Mobipocket reader software which is device dependent.
And it autoscrolls - not only that it actually will autoscroll fast enough that I can use it, and that's the first time I've EVER found software that will do that. (Backflip AT&T is crippled Android - must use Marketplace apps unless you go through some slightly more complicated steps - i.e. download the developer stuff.)
Fonts and colors are very customizable.