Which OS does your mobile run?

This will be interesting. The question is simple - what mobile OS is your phone powered by?

And something to think about: Palm and HP (both very experienced and large companies in the niche with some deep pockets) have pretty much failed with the WebOS (I have Palm Pre), which so many reviewers and critics considered to be one of the best mobile devices ever to be created. Do you think there will ever be a mobile OS in the future that will be able to seriously rival the elephants such as Android, iOS, Blackberry OS? Or is the game pretty much over?