icon图标，图片规范
总体标准
icon，启动图，需要出3套标准.一个是适配 iphone 4 @1x下面那些版本，还有一个是 4 4s 5 5S 6的 @2x，还有就是一个 6plus的 @3x。
具体大小规范
| icon size 规范 | 6 plus(@3x) | 6 | 5 | 4S | @1x |
|---|---|---|---|---|---|
| app icon | 180*180 | 120*120 | 120*120 | 120*120 | 57*57 |
| 启动图片 | 2208*1242 | 750*1334 | 640*1136 | 690*960 | 320*480 |
| app icon for store | 1024*1024 | 1024*1024 | 1024*1024 | 1024*1024 | 512x512 |
| Spotlight search results icon | 120*120 | 80*80 | 80*80 | 80*80 | 29*29 |
| Settings icon | 87*87 | 58*58 | 58*58 | 58*58 | 29*29 |
| Toolbar and navigation bar icon | About 66 x 66 | About 44 x 44 | About 44 x 44 | About 44 x 44 | About 22 x 22 |
| Tab bar icon | About 75 x 75 | About 50 x 50 | About 50 x 50 | About 50 x 50 | About 25 x 25 |
| Default Newsstand cover icon for the App Store | At least 1024 pixels on the longest edge | At least 1024 pixels on the longest edge | At least 1024 pixels on the longest edge | At least 1024 pixels on the longest edge | At least 512 pixels on the longest edge |
| Web clip icon | 180 x 180 | 120 x 120 | 120 x 120 | 120 x 120 | 76 x 76 |
| 命名规范 | File Name | Used For | Ad Hoc |
|---|---|---|---|
| 512x512 | iTunesArtwork | App list in iTunes | Optional but recommended |
| 1024x1024 | iTunesArtwork@2x | App list in iTunes on devices with retina display | Optional but recommended |
| 120x120 | Icon-60@2x.png | Home screen on iPhone/iPod Touch with retina display | Required |
| 180x180 | Icon-60@3x.png | Home screen on iPhone 6 Plus | Optional but recommended |
| 40x40 | Icon-Small-40.png | Spotlight | Optional but recommended |
| 80x80 | Icon-Small-40@2x.png | Spotlight on devices with retina display | Optional but recommended |
| 120x120 | Icon-Small-40@3x.png | Spotlight on iPhone 6 Plus | Optional but recommended |
| 29x29 | Icon-Small.png | Settings | Recommended if you have a Settings bundle, optional otherwise |
| 58x58 | Icon-Small@2x.png | Settings on devices with retina display | Recommended if you have a Settings bundle, optional otherwise |
| 87x87 | Icon-Small@3x.png | Settings on iPhone 6 Plus | Recommended if you have a Settings bundle, optional otherwise |