Don't you just hate it when you download an App Store App onto your beautiful iPhone 4, only to be presented with some ugly low-resolution app icon? I don't know about you, but the first thing I do is throw that bad boy in a folder somewhere. Can't have that ugliness de-beautifying my Retina display.
Thankfully, there are ways to convert your icons to retina-worthy icons, but those methods all required some form of end-user intervention. RetinaAppIcons is a jailbreak tweak that promises to take care of all of the dirty work for a nominal fee of $0.99 cents, but does it work as advertised?