I've read a bit about it at http://oauth.net/ , it's "a simple way to publish and interact with protected data" apparently.
I think it's exactly what I need to provide a secure way of accessing data from an android/iphone app via a REST web service, but I can't work out exactly what it is.
So, put simply, what exactly does it do and are there any (really) simple examples of it in action I can follow, preferably implementing something in c# that can be accessed from a smartphone app?