What are people using mostly to build iPhone games with? I'm learning iPhone programming. Currently I'm watching all the stanford vidcast, doing the assigments and going through the beginning iphone development apress book. I want to get into building games and want to know if developers are buidling everything with opengl es or are they using pre-existing game engines?
I believe most people are simply using Apple's APIs. Other than that, I think cocos2d is pretty popular.
Depends how graphic-intensive the app is.
If it needs a lot of graphics, go with a pre-existing engine.
If not, many use OpenGL ES
You can find a bunch of suggestions here:
learning iphone game development
Which technologies/concepts do you suggest I learn before creating an iPhone game?
I used Unity. There's been a lot of great games (even in the top 10) that used it. You don't even need to know objective-C. The code is written in scripting languages using C#, Javascript or boo and then compiled. It is expensive. It will cost you a minimum $600 for an indie license to do iPhone apps. unity3d.com
It's tough to get up to speed writing a game with all the APIs to learn and few good game examples (especially if you are new to Objective-C). I ended up tracking down the old crashlander source, which is notoriously hard to find since Apple pulled it.
There are probably half a dozen iPhone game programming books in the pipeline. Until then, the learning curve is pretty steep.
I'd suggest starting with an OpenGL 2D sprite-based game. Start by learning OpenGL ES, the touch system, then the audio system.