I have an iPhone webapp that uses a cache manifest to work offline. I add the webapp to my home screen, use it (say scroll to a certain location on a page), then go back to homescreen. When I open the app again, for a brief moment I see where I used to be (at that scrolled location on that page), but then the app "reloads" and I get scrolled to the top of the mainpage. Is there a way to prevent this "reloading"? This happens even in airplane mode (ie everything is working off the cache).
You're just seeing the default startup image, which is just a screenshot of the last place you were at. It's not "reloading"; the app wasn't loaded to begin with.
Search for "apple-touch-startup-image" to set a real loading image.