There's no doubt about it - we cover quite a few mobile phone OSes in this industry.  And they all have their various pros and cons.  Some are exceptionally great at e-mail, while others excel in the media category, while others are fantastic in the web browsing department.  At the end of the day, there's a mobile phone OS out there for just about everyone.

So, we ask you - what mobile phone OS do you use?  If you use more than one device, you can pick up to three (3) answers (if you use more than three, pick the top three that you use).  Cast your vote, and defend your OS (or OSes) in the comments!