Every iPhone application needs some icons that are displayed when certain events occur, like when some new notification comes, or the icon for home screen or the icon that is displayed on spotlight.
All these icons have different size properties but apart from their size there are some common properties they have. Let’s see them first.
The icons should be in .png format
The icons should be flat and should not have transparency.
The images should be squared, without any round corners.
For any iOS device the icons size for app store is 1024px * 1024px
Other app icon sizes are usually bases on 1x, 2x and 3x sizes for every kind of icon. For example Spotlight’s 1x icon size is 40px, hence 2x and 3x are
Spotlight icon sizes: 40px * 40px 80px * 80 px 120px * 120 px Settings icon sizes: 29px * 29px 58px * 58px 87px * 87px Notification icon sizes: 20px * 20px 40px * 40px 60px * 60px App icon sizes: 60px * 60px 120px * 120px 180px * 120px
Recently with Retina displays coming in iOS 1x images are no longer required hence only 2x and 3x image are required along with the App icon.
Below is an image showing what images and sizes are required for an iOS app.