Sound output through the provided headset is very good, and the equaliser settings have a real effect without creating a distorted noise. Even the Mega Bass setting, which can often cause sound-quality problems, is pretty good.
The headset is a two-piece job, and if you don't like the provided earbuds, which sat quite comfortably in our ears, you can use anything with a 3.5mm connector plugged into the microphone. Between this and the handset sits a lozenge-shaped controller for volume and track management, and also for the W900i's FM radio.
The radio is a disappointment, because all control has to be exercised using the lozenge and there's no software on the handset itself. You can't have pre-set stations on the handset, instead searching manually for them using the same small slider buttons on the lozenge that you use to switch between music tracks. It's a fiddle, and a big step backwards from the radio on previous phones.
The main camera's 2-megapixel capability is no different from that on the W800i or the non-musical K750i, though in both cases the 4x digital zoom has been upped to 8x. The camera controls are ergonomically placed around the edges and on the front of the handset. As with previous Walkman phones, it's great that you can turn the handset on in 'music only' mode -- ideal for a flight, when the phone must be turned off. Infrared is also a bonus. Bluetooth is great for making long-life connections with devices such as your PC or a headset, but infrared is ideal for beaming a picture to another device. You can set it as either on, off or on for 10 minutes.
Music phones are far more widespread now than they were when Sony Ericsson introduced its first, the W800i, and the competition is consequently tougher. To find a single mono speaker on the hardware is a disappointment. The internal memory too, though more capacious than ever, is only just acceptable when compared to a dedicated music player.
In general use we found that voice-call quality was good and we didn't drop any of our test calls. Video calls too were a positive experience, with the front button making it very easy to initiate calls and the screen space was well used.
The W900i delivered a strong battery life, and during the test period we were able to use 3G services and listen to music adequately for our needs without draining the battery in any one day. Heavier users of 3G or music should bear in mind that they may need to charge the W900i daily.
Edited by Mary Lojkine
Additional editing by Nick Hide