Judging by the number of tablets at this year's Mobile World Congress show in Barcelona, anybody would think that somebody had some success with a tablet device at last.

The phrase 'iPad killer' along with its predecessor 'iPhone killer' and older relative 'iPod killer' is now taken to be a sure sign that said device will do no such thing.

Indeed, we don't really expect any of the devices on display at MWC to pose a serious threat to Apple's dominance of the tablet market. But it's clear that there's a wider market than the one Apple is currently carving out for itself, and cheaper and more widely available tablet devices will surely find a firmly profitable second place.

Apple remains, however, the elephant in the room and its absence is all the more conspicuous thanks to the weight and variety of devices aping its successful tablet. Just as last year all the talk was about what Apple would release, this year all the talk is about what devices (if any) can duplicate Apple's success.

Macworld managed to get its hands on all the major tablets, and one thing is clear: Apple's got some competition. While some are clearly more adept than others; and some are obviously more ready to roll than others; there's a lot of fresh ideas coming to challenge Apple.

And fresh ideas mean progress and that's good for everybody. Here's what we thought of all the devices on test.

Motorola Xoom (Android 3.0)

HP and BlackBerry may have more interesting devices, but the one that's probably going to give Apple the run for its money in terms of marketshare is Google with Android 3.0 (aka Honeycomb). There are two devices here running Honeycomb, the Motorola Xoom and a Samsung 10.1. We managed to get more hands-on time with the Motorola so are looking at that in depth here.

Even though Google, like Apple, isn't actually at the Mobile World Congress. You can feel Google Android everywhere. It's powering half the devices and half the stalls here have Android logos or statues or other marketing material.

Android 3.0 is a reasonably large departure for Android. Like the BlackBerry PlayBook, the OS does away with the home button (something we're expecting from Apple, incidentally) but places a persistent on-screen button in the bottom-left of the screen (along with a menu and back button). On the top right you have settings and networking information and options.

In some respects the home screen for the Motorola Xoom is reminiscent of the Android phones we've tested. Present are a combination of icons to launch applications, and widgets that display information (weather, photos, mail, and so on). Touching an apps icon (now in the top-right of the screen) brings up a overview of all the apps and programs available; in top half of the screen are representations of each screen and dragging the icon to one of those displays adds the shortcut to the home screen.

Like the iPad you can attach a bluetooth keyboard to the Motorola Xoom and when combined with the docking stand it forms a surprisingly nice looking PC lookalike. You will also be able to attach a mouse to the production model (although that wasn't on display here and we're not sure how well the interface works with a mouse input).

Overall though we did find the interface more confusing than the HP TouchPad or BlackBerry PlayBook, although it's worth noting that we had more time to experiment with the Xoom than we did the HP TouchPad; and the settings menu of the BlackBerry PlayBook was locked down limiting the amount of "messing around" we could perform.

The interface was snappy, however, and we experienced no crashing or errors in our time with the device. The specs are powerful with a  1GHz Tegra 2 dual-core processor, 1GB DDR2 RAM and 10.1 in 1280x800 display.

 

Developer support will be strong for Android 3.0, which is probably it's biggest selling point. Confusion is probably it's biggest hurdle to clear if it's going to take on the pure simplicity of the iPad. There are multiple versions of Android on all different devices, version 2.2 (Froyo) for most mobile phones, a new version 2.4 seems to provide compability between phones and tablet; and the tablet itself is running Android 3.0. And then the operating system itself simply isn't as, well… simple, as the iPad.