Ask HN: Beginning to Code on the Iphone?

I've recently started learning how to develop an iPhone app, however I have relatively little programming experience under my belt. I am a pretty technical guy, but would like some advice from experienced programmers on how I should continue. The app is a game and would require sprite animation and perhaps a basic physics engine but nothing too intensive. From what I can reckon, I would need to learn Objective C, Cocoa, and then Open Gl ES. Am I correct in this assessment? What would be the most efficient way to go about this?