TomTom START: http://www.tomtom.com/en_gb/products/car-navigation/start-2-europe-black/
basic TomTom car navigation device with 3" (7.5 cm) screen; replaced the ONE series (which may still be available in some stores); comes with color touch screen and 2GB map space (one continent, @ most, very little space left for additions like voices)
extras that might be available (see further down for explanation of what an extra has):
- Advanced Lane Guidance
- Text-to-speech
- IQ Routes™ technology
TomTom XL: http://www.tomtom.com/en_gb/products/car-navigation/xl-live-iq-routes-europe-1-month/
the big brother of Start / One; has an 4.3" (11 cm) screen instead of the 3" of Start / One.
additionally to the 'xtras available for Start / One, also has
- LIVE snapshot
TomTom XXL: http://www.tomtom.com/en_gb/products/car-navigation/xxl-iq-routes-europe/
big brother of the big brother; same as XL but with a 5" / 13 cm screen. does not come with LIVE snapshot (yet).
TomTom GO: http://www.tomtom.com/en_gb/products/car-navigation/go-950-live/
is the top dog of the TomTom car navigations. on top of the XL features, includes:
- Hands-free calling
- Voice command and control
- Enhanced Positioning Technology (only available on the 9x0 (and the upcoming 1000) models)
- 4GB memory which allows to store more maps & more optional stuff (9x0 & 1000 models only)
* Advanced Lane Guidance
on highway intersections and slip roads, show a stylized representation of the lanes and marks with arrow(s) the lane(s) to follow
* Text-to-speech
speaks out the driving instruction
* LIVE snapshot
the TomTom includes a SIM chip (like the ones used in a mobile phone) to receive up to date traffic informations collected from mobile phone customers; this information is collected anonymously from the GSM antennas and includes position and change of position of many mobile phone users. that data is then sent to every TomTom equipped w/ LIVE snapshot / HD Traffic every 3 minutes or so.
Traffic / TMC
instead of LIVE Snapshot / HD-Traffic, some models come (only) as Traffic which makes use of an (EXTERNAL) radio antenna to receive TMC (Traffic Message Channel) sent out by some radio stations. TMC is updated only every 15 min (+ or -) and covers only highways.
* IQ Routes™ technology
based on the data collected for HD-Traffic users, TomTom has compiled statistics for the traffic of many roads (not only highway) for any time (5 minutes grid) over the week and depending on the season (vacations aso.)
* Hands-free calling
connects to your mobile phone with Blue Tooth and can be used to answer and make calls; calls can also be made with numbers found by the Google search service provided with LIVE Snapshot by clicking on the Call icon provided. it is also possible to import one's contact list to the TomTom & use it to make calls.
* Voice command and control
after pushing an icon on the TomTom display, it is possible to give an instruction (e.g. CALL HOME); more then 200 commands can be spoken, avoiding navigating the (sub-)menus
* Enhanced Positioning Technology
makes use of motion sensor to keep track of the car's motion in tunnels or area without sight of open sky en thus without GPS signal; thanks to this it is possible to get instructions in tunnels or between hi-rise buildings when other navigation systems would otherwise grey out and leave the driver clueless.