However, only a few tablet-specific Android apps take advantage of the Xoom's larger screen; the new USA Today tablet app does. (Two weeks ago, in my original comparison, the smartphone version of USA Today wouldn't load on the Xoom, though it did install.) More typically, "tablet" apps remain stretched renditions of the smartphone version. Amazon.com's Kindle app, for example, displays one too-wide-to-read page when in landscape orientation, rather than two facing pages as on the iPad 2. The Xoom doesn't display such legacy apps in a smartphone-sized window, as the iPad 2 does, to clue you in. Additionally, I haven't found Android apps that auto-adjust their display and capabilities depending on whether they're running on a smartphone or tablet -- a feature that has quickly become very common in the iOS world.

The Xoom and other Android tablets will need a better stable of apps to foster the addiction that iPad users exhibit with their tablets. The growing selection does show some of the promise of the tablet form factor, but none is exceptional.

. There are tens of thousands of apps for the iPad 2's iOS, from games to scientific visualization tools. Sure, there's a lot of junk, but you'll find . Android doesn't have anywhere near the same library of apps as iOS, but its smartphone-oriented apps portfolio is now in the thousands and growing, with many relevant apps such as Quickoffice, for which the Xoom includes a basic version with limited creation and editing capabilities. I often find that iOS apps are more capable than their Android equivalents (such as the Kindle app) -- but not always (Angry Birds, for example).

Both the Apple App Store and Google Android Market separate iPad apps from smartphone apps, simplifying the search for appropriate titles. The Apple store also indicates which apps auto-adjust for the iPhone and iPad, so you know they can be run on both devices and appear native on each.

Unlike Apple's App Store, the Android Market is not curated; developers will have an easier time getting their apps listed, but the market also that masquerade as banking programs or other apps and steal user information. Apple's App Store seems to be less at risk to such Trojans. The Android Market is also slower to load than the App Store and not as easy to navigate within the app details.