Depends what it is you want your "phone" to be able to do.
I personally must have:
WeatherBug (free version since that's what this thread is about)
OperaMini
GoogleSync (even though it kinda sucks, I have to have it)
Also, there's quite a few threads like this already out there, try a search and you'll come up with some things that I didn't mention. (Then again, I didn't mention them cause I don't use them!)