The front of the handset is virtually identical to the K750i in terms of button layout although their functions are slightly different. Three buttons directly under the LCD, followed by two further buttons under the left and right side of the top three buttons with the further improved joystick in the middle. Directly underneath this is the keypad, which again is identical in layout to the K750i although the keys on the W800i are slightly bigger, feel better and are more responsive when pressed.
On the top (infrared port & on/off button), bottom (charger/handsfree port), left (play/pause button & memory slot) and right side (volume control and camera button) of the handset all the keys are in the exact same position as the K750i and virtually perform the same functions, with a couple of minor exceptions which I'll come to later. The back of the handset is slightly different. The camera lens cover has been replaced with a more conventional design type for a camera cover, using a shutter rather than the 'slide' effect used on the K750i. There is a little switch which you just push down or push up in order to open/close the shutter which in turn immediately activates/deactivates the camera mode respectively.
I personally prefer this camera lens cover design style (on the W800i) to the K750i's because I found that sometimes my K750i's lens cover when in my pocket would sometimes open accidentally and therefore drain the battery whilst on camera mode. I haven't found this as yet with the W800i as the switch is far more difficult to press accidentally and requires deliberate activation before it will open. The mirror for self portraits on the W800i is also outside the camera lens cover rather than hidden by it like on the K750i. A small advantage for those that like to check their appearance or fix their make up; you can now do so without opening the camera.
The battery, back cover, sim card compartment etc are virtually the same (with the obvious colour difference) and can be interchanged on each phone as one of the pictures demonstrates.
The other noticeable physical difference would obviously be the colour. As to which colour between the two models is nicer, well this would have to be down to personal preference really. The K750i looks more corporate because of the black colour which makes it look professional. The W800i looks more sporty and bright with its white and metallic orange finish which still looks nice, but in a different way to the K750i. Plus being trade marked as a 'walkman' phone, it has the same primary colour which reminds people of another very popular MP3 orientated device made from Apple Mackintosh.
Was this a deliberate choice of colour from Sony Ericsson's design production team to draw similarities to the record selling i-Pod? Let's just say designers never deal with coincidences!
The one thing I will say for the W800i's colour is that it can easily succumb to dirt as it is such a light colour. Greasy or sweaty hands are a big no-no when using this phone. My W800i still looks very new and clean, but it'll be interesting to see how long this remains the case. I'm sure my rigorous usage demands will sooner rather than later cause the phone to show more wear and tear than the K750i.
On the positive side to dirt and dust affecting the phone, the W800i's improved joystick design does have a couple of benefits over the K750i. Firstly, the joystick is not as deeply embedded into the phone as the K750i's. This is an improvement because with the K750i, I use to find dust and dirt would accumulate in the gaps around the joystick which was very difficult to clean.
Over time, this potentially could cause particles to get into the phone which could cause it to stop working. The W800i's joystick is not as deep into the phone as it has a protective silver cover shielding the gaps around the joystick. This minimizes the likelihood of dust getting into the handset as well as allowing it to be easily cleaned and removed on the rare occasions that it (dust) does.
Secondly, the joystick on the W800i actually feels better and works just as well as it feels. Don't get me wrong, the K750i's joystick was an improvement from previous Sony Ericsson models and works very well. The W800i continues this evolution and is more responsive and feels sturdier than the K750i; an impressive design.
That is pretty much it in terms of physical differences so lets look at some of the features differences between the W800i from the K750i:
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