Aesthetically there are a few other minor tweaks, but ones that enhance the overall look of the unit. To match the black back, all the hardware buttons around the sides are chrome coloured instead of black. There's no change to the composition of the buttons, though, with a volume rocker and silence switch on the left and a hold/power button on the top. Even more subtle is the bezel, which is ever so slightly thicker due to this model being 1.1mm wider than the original. Overall, the iPhone 3G is every bit the exemplary piece of design and engineering the original was and its slimmer looking exterior only enhances this.
Having covered the main hardware change over the original iPhone, it's about time we talk about the other: GPS. As with many phones the iPhone 3G utilises Assisted GPS (A-GPS) that uses both GPS satellites and nearby mobile phone masts and Wi-Fi hotspots to triangulate your position. This, as seen on the Nokia E71, can work very well indeed. In our neck of the woods we found it could take a minute or two to get a fix on your current location, but in built up areas where it's less reliant on GPS it's far quicker. Once fixed on it works very well and tracks your location easily be you on foot or in a car. It's particularly handy if you're lost on the road or in the city and also enables various applications to use this information for geo-tagging and location sensitive services.
It doesn't, however, make the iPhone a full fledged GPS device in the way a TomTom is. First and foremost there's no software to enable such functionality and if and when such a thing does exist one suspects the in-built speakers, though more than adequate for ring tones and other alarms, aren't loud enough for giving directions in a noisy car.
Nonetheless, the implementation of A-GPS on the iPhone 3G is pretty good. A full fat GPS device it might not be but you can program routes using Google Maps and provided you know roughly where you're going, it's certainly useful for finding your way in the fiddly bits towards the end of any journey.
Whether it could ever be made into a genuine GPS device is up for debate, but a lot of work would be needed to make it better than the likes of the TomTom One, Navigon 2100 or the Route 66 Mini Regional Sat-Nav – all of whom can be had for £100 or less. It's also worth noting that using the GPS extensively is one of the more battery draining features so prolonged use will severely curtail longevity. With all these factors combined you can colour us sceptical.