So you may have a few older iPhone app icons on your shiny new iPhone 4 that haven’t been optimised to utilise the iPhone 4’s Retina Display high-res icons, but there is a way of converting those old iPhone app icons.

According to an article over on iPhone Download Blog by Sebastien, an “anonymous” tipster has given they a tip on just how to convert hose older iPhone app icons; however you’ll need a Jailbroken iPhone and a couple of apps.

So here’s how to convert old iPhone app icons to Retina Display icons…first of all you’ll need to download Resize-Photo from the App Store and iFile from Cydia. Once done, in iFile go to the folder of the app that you want to optimise the icon, usually names appname.app.

Next you save the application icon to the camera roll and should be sized 512 x 512, then open Resize-Photo and change size to 114 x 114 and save. Now go to iFile and go to your photos folder and copy the resized icon, then go back to your app folder, look for the app icon and rename it just in case anything should go wrong.

While in the app folder, paste the resized app icon and name it Icon.png or whatever the original name of the app was called, and then reboot the iPhone and bingo you’re done, you should now have a high resolution icon, although apparently you may need to try a few ties because this trick doesn’t actually work with every app icon.