Well, progress is going a little slower than anticipated, mainly due to the fact that I finally got into the Starcraft 2 beta, so my spare time is being split between Anguna and Starcraft. But that aside, things are going fairly well.
The framerate issue from before is trivial to fix, so that's been addressed.
Performance was more interesting. If I render the entire background every frame like I planned on doing, things USUALLY worked fine, but would occasionally get sluggish if the device was doing stuff in the background (checking mail, getting push notifications, doing whatever else that crazy thing does). So I decided as a workaround to prerender each background to an offscreen surface, then just blit that to the main display every frame. Which worked fine, except that there was some sort of odd behavior in the graphics system where it wouldn't actually destroy/release memory from offscreen surfaces when I was done with them (or at least do so in a timely fashion), so after about 10 room transitions, I'd run out of memory and crash. Of course, since it was only on the device, it took quite a while to figure out exactly what was happening. Turns out Apple has a nifty tool called the Iphone Configuration Utility which, believe it or not, actually runs on windows! It lets you view the device console logs in real time, which was amazingly helpful in tracking down the issue. Fixing it was then just a matter of reusing the same offscreen surface for every room, drawing over the last one, instead of destroying and recreating them with each room transition.
I'm also running into long load times -- I'm not sure how I managed to see only 5 seconds before, but it's often taking 7-10 seconds to load the resources for the game, and that is with them being marginally broken up. That's a bit higher than I'd like. I think that I might be able to reduce the perceived load time by doing part of it while showing a splash screen, doing some more at the game start, etc, but I'd still like to get that a lot lower.
Overall, though, things are running well. The first dungeon is completely working (although a lot of the UI to make it really play right is missing, such as life bar, subscreen, button for activating secondary item, etc), and the first little chunk of the overworld is mostly functional. (the graphics for the bridge to the desert area are messed up right now).
I really need to start messing with the UI now. Which should be a lot easier than it was on the GBA or DS, but still a good amount of work, as it's going to be completely different than the GBA UI, meaning a lot of it will have to be completely rewritten from scratch. So that's my next task....(well, after I play some more Starcraft 2).....