Ryan Paul - the new Developer Evangelist at Xamarin) - has a great long-form piece up on his "old job", Ars Technica, about LinkedIn's mobile app, and how they have architected it.
No one knows more about this paradigm shift than Kiran Prasad, LinkedIn’s director of mobile engineering. Prasad was one of the key players in LinkedIn's efforts to resurrect its mobile offerings, and he was kind enough to walk Ars through the process.
They are using a hybrid app - HTML and some native. That makes some sense for them, but you could also argue that it made sense for Facebook, before they went all in on native. Maybe Ryan could pursuade them to use the Xamarin tools :)