TomTom car kit for iPhone

The wild popularity of the iPhone shows no sign of lessening, nor is the vast array of turn-by-turn GPS navigation applications available in the iPhone App Store likely to decrease. TomTom is the first to come to market with a car kit mounting solution for the iPhone that also aims to improve GPS reception.

The TomTom car kit for the iPhone is a docking mount that attaches an iPhone 3GS or iPhone 3G to any car windscreen. Looking much like a regular GPS window mount but shaped to fit the iPhone, the TomTom car kit also includes a built-in GPS chipset that the company claims enhances the iPhone's often-erratic navigation performance.

The car kit uses the TomTom's EasyPort mount system. This suction cap attaches the car kit to your window simply by pressing and turning the dial. It's also easy to remove — simply turn the dial in the opposite direction and pull it off.

The TomTom car kit for iPhone is made of matte and glossy black plastic. The ball-style hinge holding the suction cap is fully rotatable and the phone can be positioned in either portrait or landscape modes. It feels reasonably well built for a device of this kind. Unfortunately, the car kit can't mount an iPhone with a case attached.

On the right side of the TomTom car kit for iPhone is a 3.5mm audio jack and a mini-USB connection. The audio jack enables you to wire the sound to your car stereo if it supports a line-in connection, though TomTom stingily doesn't supply a standard audio cable to do so. The mini-USB port powers the car kit and a standard car charger is included in the sales package. On the left side a volume rocker adjusts audio levels for the car kit's built-in speaker.

Our experiences with the TomTom car kit for iPhone were largely positive. The iPhone snugly clips into place and the car kit doesn't rattle, vibrate or move while you're driving. This is an issue we've found with many cheaper window mounts for the iPhone and can make it hard to see the screen.

GPS performance is very impressive — to put it simply, pairing the TomTom car kit with any of the available turn-by-turn navigation applications puts GPS performance and reception on par with any dedicated portable navigation unit we've reviewed. The iPhone's GPS performance is known for being erratic, but the car kit effectively eradicates this issue. Our position on the map screen was, in most cases, almost perfect.

The TomTom car kit's built-in speaker is significantly louder than the iPhone's. The car kit also allows you to take calls using a built-in microphone. This is a handy function, but we found we had to lean forward and speak directly towards the dock to get acceptable outgoing audio. If you have a Bluetooth car kit installed, the audio can be transmitted through your car speakers. Anyone without one and without a line-in audio jack on their head unit is out of luck — the TomTom car kit for iPhone doesn't include an FM transmitter. The car kit can be used without the included car charger, but if it's plugged in it recharges your iPhone.

Conveniently, the TomTom car kit for iPhone will work with any GPS navigation application available in the iPhone App Store — in addition to TomTom's own app, the car kit will work with Navigon, Sygic, CoPilot and NDrive apps, as well as any future GPS navigation apps.

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