O2 has been selling Xdas for many years, but the Zest is something new, being the first Xda to be available on Pay As You Go (PAYG).
The device is a bit squat in the hand, but its 2.8-inch screen is clear and sharp, thanks in no small part to its 480 x 640-pixel resolution.
O2 has put a menu system on top of the Windows Mobile 6.1 today screen and this gives you a finger-sweepable way to get at often-used apps and services.
The main screen offers the time and weather. Sweep left to right for a grid of contacts. Sweep again for a 3 x 3 grid of shortcuts to applications and settings. Make a final sweep and you are back at the time screen.
The Xda Zest is a 3G device with HSDPA and a front camera for video calling. The main camera sits on the back of the casing and shoots stills at 3 megapixels, but has no camera or self-portrait mirror.
We like the Hold button on the right edge of the casing. This turns the screen off and locks the buttons, and is far superior to the software-based lock system that exists in Windows Mobile 6.1 because you can access it at all times.
We also like that GPS and Wi-Fi are here, and PAYG customers may find the latter particularly useful.
Build quality is mediocre and there is nothing here to lure upgraders, unless their existing Xda is quite old, but this is a competent everyday device nonetheless.