Time to slip the iPhone in: ours fitted flawlessly in the cradle, cushioned by a soft round pad as well as a rubber overlay under the top arm to avoid scratches. On the left side of the cradle you'll find the volume switch for the rear-mounted speaker -- which is significantly louder and clearer than the iPhone's -- and its audio-out line jack, which is right next to a mini USB port for power. We almost missed the pinhole mic just below the dock connector, which worked fine for our driver when he took a call using the hands-free functionality. One of the more impressive features of this car kit is the flexibility of positioning the iPhone: the cradle can slide lengthways and -- for the sake of the app's landscape mode -- can also rotate 360 degrees freely, but it's detented, so your iPhone won't be spinning around while you do a few donuts on the tarmac. Flip over the car kit and you'll see the same EasyPort Mount as used with the TomTom ONE and TomTom XL, connected to the main body by a convenient ball joint. We found the suction pad to be very easy to use: a simple twist on the dial tightly secured the entire kit onto the glass or the supplied sticky disc for the dashboard, and releasing it was just a matter of untwisting the dial and then pulling the plastic tag like you do with most conventional suction pads.
So we're impressed by the car kit's hardware, but what really matters is its GPS performance. To see the difference we installed the TomTom app on two iPhones and placed them side by side on our dashboard: the iPhone 3G connected to the TomTom car kit, while the 3GS used its built-in GPS receiver and sat on a generic phone cradle. Sure, the two phones are different, but we know they share the same Infineon GPS chip, and we thought it would be interesting to see if the car kit can compensate the 3G's slower processor. In our first round of tests we drove around the motorway and intercity roads, and the only significant difference we noticed was that the car kit provided a slightly quicker positioning, shouting out instructions at more sensible times when approaching junctions. The 3GS sans car kit didn't do too badly, but had we driven any faster in the city streets we would have missed a few turns. See for yourself in the video below.
We had a feeling that the car kit would make a bigger impact on the smaller streets, so to prove this we ran a torture test in Central London: we left the route planner on and drove around small streets randomly to test the GPS' accuracy and speed. The result? Again, the car kit proved to be quicker -- even with the slower phone -- and more accurate most of the time. Depending on the complexity of the route the iPhone 3GS' faster processor may even save a further two or three seconds when used with the car kit.
There's no denying that the TomTom Car Kit for iPhone can make your life a tad better, and it's also a much better looking iPhone cradle compared to a generic-style holder. For those often driving around small city streets you'll get a greater benefit from the car kit, but at a dear cost of $119.95 for iPhone or $99.95 for iPod touch (neither of which includes the app), it's probably worth it if you're still stuck with a GPS-less first-generation iPhone or any iPod touch
, provided that you don't mind the lack of a compatible TomTom app for the time-being. For the rest of us, we'll just get a standalone TomTom device, thanks.