I had months of data stored in this app and now it is all gone. No warnings when you updated that you need to backup your data. Now its all gone and Im out hundreds of dollars because of a hack programmer! Avoid like the plague!
UPDATE & FIX
For those who did lose data, it may be recoverable. It turns out that it has nothing to do with IOS5, as the programmer states. The problem is that the programmer renamed the "IouTableArray.data" file to "iouTableArray.data". Its a case sensative file system (always has been), so the update is looking for a file that starts with little "i" and cant find it, so it creates a new file, which makes it appear as if all your data is gone.
Fortunately, it may still be there. Use a program called iExplorer to browse the files on your device. Look for Apps|com.Sabeni.iouapp|Documents. Copy the old "IouTableArray.data" file to your desktop by drag and drop. Rename it to "iouTableArray.data". Power off you device (hard reboot). Power on and reconnect with iExplorer. Use it to delete the "iouTableArray.data" from your device. Now copy the file you renamed from your desktop to device (drag and drop again). DONT start the app to see if it worked. Power cycle again (another hard reboot). Now power up your device, start the IOU app, and all your data should be restored.
KYThrill about IOU (I Owe You)- Track Money