How to record/stream iPhone 4 screen with iOS 7?
Unfortunately the use of such software has a pre-requisite of AirPlay Mirroring, which is not supported by an iPhone 4 at any OS level, hence teh requirement for an iPhone 4s minimum. If you had a device that supports it, then it's pretty straightforward (take a look at this answer elswhere on AskDifferent) but with an iPhone 4, you are out of luck unless someone can suggest a way of enabling it with a Jailbreak hack.