Grandcentral is Google's VOIP phone service (sort of). After logging in you can click a personal to call in the residential United States and it will ring your home/cell/work/SIP phone and then connect you with the caller in your address book. Initiating the call from a windows mobile device means logging into the mobile website which is a hassle. The app should simplify calling a number using the grandcentral service and work on Windows Mobile 5 & 6.
This has been accomplished already for different groups. There is a firefox addon here [login to view URL]
There is an iphone app made for it here [login to view URL]
Nokia / Internet Tablet devices here [login to view URL]
The app needs to be able to dial any submitted number like the firefox addon! It should be able to login using a saved username/password to the grandcentral site and present last call details. It should be in working condition upon receipt and should be in CAB form for a wireless download & install.