TomTom offers two types of products: navigation devices and navigation software for installation on mobile devices. The navigation devices and portable devices with installed software are referred to as units.

TomTom units provide a flying interface with an oblique bird's-eye view of the road, as well as a direct-overhead map view. They use a GPS receiver to show the precise location and provide visual and spoken directions on how to drive to the chosen destination. Certain TomTom systems also integrate with mobile phones using Bluetooth, traffic congestion maps or to actually take calls and read aloud SMS messages.

In most cases, the differences between the different models is on a software level. The hardware (at least inside the unit) is relatively similar across the entire range, with the exception of certain functionality such as FM transmission, Bluetooth, handsfree calling (requires microphone) and enhanced positioning technology (done through motion sensors in the device).

Because of the restriction being mostly software based, some people have been able to upgrade their software to a top end model, using low end hardware (such as a ONE XL or GO 510), and getting most of the functionality of a brand new top of the range GO 940.

The global slogan for TomTom is "the smart choice in personal navigation". In the United States and Canada, they currently use "Go confidently". The UK slogan is "Find your way the easy way". A past slogan used in the United States was "The number one-one GPS-S in the world-world".

Source: Wikipedia