Use this Hotpot service to resize icons and images for iOS, macOS, Android, Chrome, and other platforms.
For instance, iOS requires over 25 app icons, ranging in size from 16x16 to 1024x1024. iOS also mandates retina images at 2x and 3x resolution while Android requires support for 4x (xxxhdpi), 3x (xxhdpi), 2x (xhdpi), 1.5x (hdpi), 1x (mdpi), and 0.75x (ldpi) drawables. Thanks iOS and Android overlords! Supporting multiple devices and battling these amazingly talented developers is evidently not enough of a challenge.