Just bought an HTC Wildfire from T-Mobile and using Google Calendar, Tasks and Gmail that automatically syncs with my various PC's. Also use FriendStream to get Aviationsafety,Flyontrack, Airspacesafety and other news streams as they happen.
Regarding apps try FlightWatchLite for simple METARS, AviatorJoe WxFeed or TAFsMETARs21 for TAFS and METARS, FlightToolsE6B or the All-in-1-Calc for conversions, BBDensityAltitude Pro (still in development), Time Calc for hrs, min, sec conversions, iMap Waether gives local wind, temperature, humidity, dew point, sunrise and sunset, Sundroid just for sunset/sunrise times, Siderial Clock for UTC etc and of course you can bookmark
Wind Map - Britain Observations to get the complete UK wide wind map.