Hackapalooza: making the iPhone main screen scroll!
All the buzz this evening is about developer "lg" and his wild plunge into customizing SpringBoard, the home screen application you see every time you power on your iPhone. Turns out he figured out how to burrow inside SpringBoard and get it to scroll so users don't have to use cumbersome application launchers and dock extenders. SummerBoard currently extends SpringBoard to add scrolling and wallpaper, with further features promised in future releases.
The secret seems to lie in tricking SpringBoard into loading custom routines and seizing control of the application through the back door. Lg calls his modified system "SummerBoard", a name I find especially droll--although I think "SpringRoll" might have better described the software.
Now to the down and gritty. This is a first release. It's pretty cool but it's still a first release. I ended up rebooting my phone 5 times before I got it working. I had to launch an app, and then force-quit it by pressing Home about 4-8 seconds. Then it worked really well. So keep looking for updates. It's still getting debugged.
Lg says the software works by loading items into memory after launch. I took a look around and found /Library/SummerBoard.framework. This contains an alternate com.apple.springboard property list, a short dynamic library and a framework file. This seems to be what gets loaded upon launch on top of SpringBoard.
Congrats to lg for this clever hack.