Review: Motorola Backflip
Android's default web browser is based on WebKit and can render full HTML web sites. The browser is very capable and works well on the Backflip. Other than the baked-in Yahoo home portal, I didn't notice any other AT&T or Motorola customized features. Oh, except for the presence of Yahoo's crappy search client.
Browsing speeds over AT&T's 3G network were good. Other phones on AT&T's network do better.
You can customize the Backflip about as much as you can customize any smartphone platform. Wallpapers and ringtones are easily altered. You can rearrange all of the menu items, clutter up the home screen with icons and more.
There are pretty robust ways to control the security of the Backflip, how applications are managed, how the microSD slot is managed, how data is synchronized, how location information is reported and on and on.