As the number of devices support by iOS grows, the list of icons needed when submitting an iPhone app grows. Here’s a list of the icons and the default filenames that you’ll need:
| Size | Name | Description |
|---|---|---|
| 512×512 | Whatever | Used on app store |
| 57×57 | Icon.png | Default icon for pre-iPhone4 devices (non-retina displays) |
| 114×114 | Icon@2x.png | Icon for retina display devices |
| 29×29 | Icon-Small.png | Small icon for use on non-retina displays |
| 58×58 | Icon-Small@2x.png | Small icon for retina displays |
| 72×72 | Icon-72.png | iPad icon |
| 50×50 | Icon-Small-50.png | Icon displayed in search window |
Note that the default filenames can be overridden with the info.plist icon-files entry.
The official list is on the Apple developer site: Technical Q&A QA1686.
An easy way to create all of these icons is to start with a 512×512 image, and then export it in each of the smaller sizes. I’m a Photoshop user, so I use ‘Save for Web & Devices’ in the File menu, but just about any image editor should have the ability to do this.