ok tech heads...

how do i get messenger on it?

what do i need for gps/nav?

IIRC it already comes with Messenger - you should just need to log in (assuming you have a SIM card in it and your O2 contract allows GPRS.

For Nav i would go and buy TomTom3 with either the 'wired' GPS kit (ie GPS receiver plugs into cig lighter and device, with aerial sitting on dash) or the bluetooth GPS kit. You can also get a TomTom kit with a cradle as well which is OK. If you want to go to town then let me know and i will point you in the direction of some excellent in-car kits by brodit for the XDA-2.

I would recommend the wired kit as it keeps the xda charged up and therefore you can keep the screen on all the time with the backlight which means you can see it! Bluetooth GPS isn't connected to the device so unless you have a car charger, the device will keep going into powersave which beleive me is WELL irritating! If you turn powersave off and the screen backlight on, then the bluetooth will drain the battery in 5 minutes flat!