The Sony Ericsson Z750i was announced toward the end of Q1 2007 and it marked the Japanese-Swedish company's foray into the HSDPA market. At this time, if you're thinking the Z750i looks familiar, it is. In fact, you'll be hard pressed to find any major differences between the Z750i and the earlier Z610i.

Design of the Sony Ericsson Z750i Mobile Phone

We have to admit sheepishly that we really like the stylishly designed Z750i. Part of the reason, we suspect is the Japanese "kei tai" (mobile phone) allure which has typically followed the clean and simple design philosophy.

Like the Z610i, the Z750i retains the seamless mirror-like surface with a hidden OLED screen. When activated, the screen illuminates to give the effect of a floating display on the surface. If you look at it from an angle, it appears as though the various "layers" of the screen extends into the handset, giving it depth and a three-dimensional feel. The OLED screen displays incoming message alerts and calls, music information and in idle mode, the time, battery level and signal strength.

The only cosmetic differences we find between both handsets are the Z750i's matte-plastic backing, taller spine (the part of the bottom lid that extends above the top cover), inclusion of call/end keys and the slightly different layout of the buttons.

That said, the buttons on the Z750i are easily one of the best in the market today. The alphanumeric keys are large and provide excellent tactile feedback. The rest of the control buttons are also adequately sized to provide reasonable sense-of-touch. There are three quick access music controls on the left edge of the handset. Two of these buttons double as volume keys.

The Z750i is not only aesthetically pleasing on the outside, the cascading flow of lights starting from the bottom of the keypad and ending with the lighting up of the 2.2-inch LCD screen is also a very nice finishing touch. Obviously, those with a chronic habit of wiping their handset may get deliverance with this Sony Ericsson, since the huge glossy surface requires constant cleaning.

Features of the Sony Ericsson Z750i Mobile Phone

Although the Z610i and Z750i are like peas in a pod on the outside, the latter is more advanced in terms of features. For example, the quadband Z750i is now on the GSM 850 frequency and it also offers triband HSDPA which add to its network compatibility in the US.

A little less known fact of the Z750i is that it comes with built-in A-GPS receiver. This is a little different from Nokia's N95, E90 and the 6110 Navigator which have built-in GPS chips. The Z750i relies on an assistance server such as a cell phone tower to triangulate the user's position. According to Sony Ericsson, this feature requires the telco operator to activate the A-GPS capability and, from what they understand, only Chunghwa Telecom in Taiwan has enabled this feature. They added that the A-GPS receiver can also connect to GPS satellites, although it will take a longer time to get a location fix. We tried the A-GPS feature during our review, but we never managed to triangulate our position. The way we see it? The proposition of the A-GPS here is somewhat dodgy and we recommend users to take this with a huge pinch of salt.

On the brighter side of things, Google Maps is preinstalled on the device and you can use this as a standalone app. However, not all the features are enabled and traffic information is one of them.

The Z750i features the new media interface which we've been talking about in the K850i Cyber-shot and most recently, the K630i. Media files are classified into photo, music and video and within each of these broad categories, there are additional options. For example, you can view camera images sorted by date, browse through albums and also tag photos. In music, files are sorted by artists, albums, tracks and playlists. The look of the media browser follows the one on the phone and there isn't an option to use different skins. Only one option is available in the settings and that's to switch orientation of the screen. Our guess is Sony Ericsson may introduce future software upgrades to enable the use of individual themes for the media browser. The Z750i also supports Bluetooth stereo for listening of music via our wireless earphones.

On the entertainment front, this Sony Ericsson comes with built-in FM radio which was missing in the Z610i, though it works only when a wired headset is plugged in. There are three games installed on the Z750i: Investigators, QuadraPop and Sims 2. Yes, Sims, the one that you get to play God or live the alternative life, though obviously it's a more stripped down version for mobile phones. That said, we think it's one of the most interesting games preinstalled in a handset, especially when the Z750i isn't a gaming-focused device like the Nokia N81.

Unfortunately, Sony Ericsson stuck with the 2-megapixel camera for the Z750i similar to the one on the Z610i. Even though it isn't a Cyber-shot phone, the lack of a built-in flash light and autofocus capability make it rather lacking in the digital imaging aspect. At maximum resolution, digital zoom is disabled and there isn't an option to set the resolution for videos though we can specify whether it's meant to be sent as a picture message or saved as a clip. Like the Z610i, the main camera lens is prone to dust, dirt and scratches due to it being exposed with no cover. For 3G video calls, there's a secondary shooter above the phone's LCD.

Performance of the Sony Ericsson Z750i Mobile Phone

Overall, the performance of the Z750i was nothing to shout at. While the phone was pretty responsive when opening applications etc, running multiple programs such as music playing in the background and texting a message slowed the handset's response significantly.

Picture quality was a mild disappointment. Granted that the Z750i isn't positioned as a camera-phone like its Cyber-shot counterparts, picture quality from the 2-megapixel camera was constantly marred by a watercolor effect. The lack of autofocus also contributed to numerous out-of-focus shots during our tests. At best, we'd give the Z750i's camera an average rating.

The Z750i is rated for 10 hours of talktime and slightly over 16 days on standby. With regular use of sending text messages, making phone calls and listening to music, the 930mAh Lithium-polymer battery lasted for two days tops before it had to be juiced. Audio quality was decent and we had no problems piping music to our HBH-DS980 Bluetooth stereo earphones during our review.