Not sure which forum this would go under but I'll post here.

I had this one app that I bought back in april that worked great. When the developer rolled out the update for the app, I was on iPod 2g (mc) iPhone os 3.1.3 and there were no problems. However the app (it was one of the wifi utilities) was pulled before the developer could update it for bugs. Although it worked perfectly fine, ios 4.0 update broke the app so I couldn't open it until I was already connected to wifi.

I ended up trying a few things to get it to work and ultimately lost the most recent version when I downgraded the app by restoring the older version in recycle bin. The older version sucked in terms of UI and dd not have the functionality it needed.

After I jailbroke ios 4.0, I have have looked for four different methods to fix the older version by using it as a shell to update it with the cydia app. Of the four methods, three failed and most recent method was the most successful.

In the last method, I replaced all of the files of the wifi app except for the code resources and info.plist. After that I deleted the older version on the computer and synced my touch and the app downloaded to iTunes but then told me that it could not reinstall because it was not "signed". As a result I ended up restoring the older I deleted

For the fourth method, I thought about figuring out what I need to edit in code resources or info.plist to trick iTunes into thinking that the app it was receiving was an upgrade to the older version. The main problem is I don't know how to code or what to edit/replace. At this point I'm trying to figure out if it is feasible in a way that it allows an upgrade and would let me install the app on non jailbroken idevices.