We Apple users are picky about our aesthetics. Some of us try to pretend that we aren't, but we are. Things like app icons matter to us. Apple doesn't make it easy to customize your iPhone's look on a system mod level, but luckily there are still jailbreak-free hacks out there to taunt Apple's need for aesthetic control.
I'm going to walk you through how to manually change app icons on your iPhone without jailbreaking. There are multiple reasons you may want to change an app icon; you think the developer's icon is ugly, you want a retina display-compatible icon, or you just want to mess with your friend while he's away from his phone. Here's how you do it: