Sorry if this was already mentioned, thread is too long to read.
to get a newer apps to work on your old device heres what you have to do.
1. locate an app in your filesystem, usually an itunes folder with all your apps.
2. rename the IPA to ZIP
3. open the zip folder, locate info.plist
4. open info.plist using a text editor, and in the description where it says minimum IOS change to the IOS of your old device.
for example if its MinimumIOS6.0 change it to MinimumIOS3.0
it works for almost any app, i just came across 2 or 3 out of about 200
enjoy!
Serge.
PS. Nothing illegal here youre just making your product compatible with your device again, which is what you have already paid for and have all the rights to do so.