There are two firmware components to the xda. The ROM (v3.17.03) which is the operating system plus built in applications, and the radio stack (4.21) which controls the communication functionality of your xda.
O2 Smart Menu, providing one-tap access on the Today screen to email, SMS, Internet and WAP browser
Enhanced GPRS operation – faster connection and higher transfer speeds
Use the xda as a modem when connected to a laptop
Contact name is displayed when text messages are received
SIM Toolkit compatible SIMs can now be accessed via SIM Toolkit program
Please note this is specific for the O2 XDA, a version of QTEK1010, and local implementations may differ. Don't apply this to QTEK 1010, T-Mobile PC Phone and other based on the same model.