I just came upon this Hanselminutes episode from back in February with John Sonmez about MonoTouch and Mono for Android, and it even mentions PhoneGap. If you are interested in working on iOS with any tool, I recommend you listen to the podcast, as he discusses the pros and cons of the different levels of abstraction and how to get the most out of the level you choose.
What do you think about his points on the different levels of abstraction? Remember, whatever level you choose we’ve got you covered with Data Abstract and RemObjects SDK for Xcode, .NET or JavaScript.