Compared to the majority of other touchscreens, the KU990's screen is very responsive and can be set to vibrate when you touch it, which provides more tactile feedback than when you simply tap a flat display.
Similar to the LG Prada's interface, the KU990's software interface features finger-friendly icons and an attractive layout. Many reviewers have said they found it difficult to tap the small icons but we didn't have any problems with them at all.
Dialling and messaging is straightforward via a numeric or alphabetic keypad that works identically to a standard mobile phone keypad minus the mechanical keys, and is aided by the vibrating feedback feature. The messaging interface also allows for handwriting input but we found it slower than just tapping the virtual keypad.
The KU990's proprietary Web browser is one of the best browsers we have seen on a mobile phone. Similar to the iPhone's browser, you can view full-sized Web pages at a reduced size and then zoom in on the sections you want to see properly.
Web pages loaded relatively quickly but we did notice some lag, which may have been caused by network issues or possibly our review unit. The KU990 comes with HSDPA, so theoretically you should be able to download pages at up to 1.8Mbps, which is almost as fast as many people's broadband connections at home.
There's no Wi-Fi, which is a shame but if you're on a flat-rate data plan then we think HSDPA is a better option, otherwise watch out as data charges can be hefty.
Interestingly, you can upload videos directly to YouTube and download them too, but unfortunately our review model didn't have the app pre-installed so we're not sure how well it works. We're assured it will be installed on the final model.
We could test out the camera though, which curiously can shoot video at 120 frames per second. At first we weren't entirely sure why this was necessary but it's actually great for capturing fast-moving action and then viewing it in slow motion, as shown in the video earlier.As for taking normal pictures, the 5-megapixel camera is very capable and of a similar quality to the Nokia N95's camera. You can adjust the size of images, picture quality, ISO and white balance, among other things.
The digital stabilisation feature reduces blur but don't expect the same level of quality as optical stabilisation. Equally, although the KU990 has a xenon flash, we didn't find it as bright as a standalone camera's flash, but it is better than an LED photo light.