How to avoid updating Camera+ 1.2.1 app to retain volume shutter

I love TapTapTap Camera+ 2.0's faster startup and new features, but I love version 1.2.1's volume shutter button more. To avoid constantly being prompted by iTunes to update to version 2.0, I made a backup copy of Camera+ 1.2.1, and then renamed the original, viz:    ~/Music/Mobile Applications/Camera+ 1.2.1.ipa  →  ~/Music/Mobile Applications/Camera+ 2.0.ipa Now iTunes no longer prompts me to update Camera+ and I retain v 1.2.1's volume button shutter release.  Background: Camera+ VolumeSnap: Rejected  9 Aug 2010, John Casasanta, TapTapTap   Camera+ pulled from App Store over hidden feature  12 Aug 2010, Aulia Masna, Macworld.com Camera+ returns to App Store with version 2.0  22 Dec 2010, Jesse David Hollington, iLounge.com  (albeit less Volume Shutter) Apple Doesn’t Want Coders Messing With iPhone Buttons – Sometimes  27 Dec 2010, Brian X. Chen, wired.com