Hum, well, a lot of the momentum on the Panda3D/iPhone project has been lost recently. You can still build it for iPhone, but it will be an effort, and it might not be the best place to get started if you’re not already experienced with building large C++ projects.
You need to use ppremake to build for iPhone. You could start by getting the Panda3D source and first using ppremake to build it for your local development environment. If that goes well, then try to build it for iPhone.
To do this, install the iPhone Developers SDK from Apple, and add:
#define BUILD_IPHONE iPhoneOS
#define HAVE_GLES 1
to your Config.pp. You’ll also need to obtain build any third-party tools you want, like libjpeg or libpng, for iPhone. But you can omit these at first, just to get started. You might need to explicitly turn all of these off with “#define HAVE_JPEG” and so on for each package.
If you want to run Python apps, you’ll also have to compile the Python interpreter for iPhone. This is surprisingly difficult, because the Python codebase isn’t designed for cross-compilation (it wants to build the interpreter and then immediately run it to build some more, but this isn’t possible in a cross-compilation environment).
If you want to run just C++ or Objective-C apps, though, you should be able to do this directly from the Panda build.