To use real-time TomTom PLUS services (Traffic, Weather) or extra downloads, you can use your mobile phone. Mobile operators generally charge you for data you download via GPRS, EDGE, or UMTS. Rates for retrieving data while roaming internationally are often charged at a higher rate. To avoid additional costs via your mobile operator we recommend downloading large files via TomTom HOME and not via your mobile phone. For example, download a map from our portal before you go on a trip.

Check with your mobile operator for details of data charges. Many operators offer data bundles at cheaper rates. The information that is exchanged between the Traffic Server and your device is minimized through compression and smart filtering algorithms, so that communication costs are minimal.

See also:
How much data traffic does TomTom Traffic generate?
Do I have to pay to use TomTom Buddies?