ResizePixel - Free image editor to crop, resize, flip, rotate and convert images online
EasyAppIcon - EasyAppIcon helps you to create your own app icons easily. Supporting Android Adaptive Icon!
App Icon Maker - Create icons for mobile app stores online for free.
favicon-generator.org - Generate icons for website and mobile app stores.
App Icon Generator - Generate icons and images for mobile apps, android and iOS. No need to upload or download. Works on your browser
Flat Icon Generator - Create stylish, flat icons for Android apps.