I upgraded my phone just over a month ago to an android.
I was using this phone before, but I upgraded to this phone. I am pleased with the quality of Google's mobile operating system. It is much better than Nokia's Symbian OS, and I find it to be better than both iOS and BlackBerry.
What I wanted to know is what kind of Apps you find are (more or less) necessary to function.
The apps I find improve my phone are:
Avast! Mobile Security
Light Flow lite
Advanced Task Killer
But I also have Facebook and Wikipedia and some games, and Skyfire Browser, and use Smart Actions.
EDIT: I was not attempting to belittle Apple or RIM by saying that Google's OS is better, I have an iPod Touch and a BlackBerry Playbook. I was stating that I prefer my Android over the others.