Start menu: See who's online, invite friends to join a session, join friends in their session, start Jobs, settings such as who is allowed to use your car or mic restrictions to friends/friends+crew/everyone etc
Phone menu: call friends - starts a private call, not heard in the general game. It only appears to work if both parties have a working mic, and are currently in free roam, not in the middle of a mission. $10 a call, even if it comes back busy or no answer. I tried phoning Truth, bOnEs, Massacre, and a couple of the others last night but the only call that worked came from Fanboy/CFO Charles. At least one call worked.
As mentioned nearly everywhere, use the phone to access online banking to deposit funds ASAP without having to find an ATM. Do it after every mission.
Pause menu: quick launch a race, check inventory, share funds from a job
I've bought a bunch of clothes but until I have a safehouse the only way to change clothes is in the stores. When I created my character for the first time on Tuesday night, I couldn't connect to the tutorial, so I backed out. It did save my character (feel sorry for all of you that had to remake your character over and over), the only thing that didn't stick was the iGTA crew logo on my left boob. If anyone sees how to enable crew emblems on clothing or other items, let us know.