What are some alternatives?
IconStore - Free icon packs by first-class designers
AppIconizer - Icon generator for App Store & Play Store submissions.
Flat Icon Generator - Create stylish, flat icons for Android apps.
IconBros - Free and continuously growing high quality icons
EasyAppIcon - EasyAppIcon helps you to create your own app icons easily. Supporting Android Adaptive Icon!
Appicon - Generate app icons and AppStore screenshots with just one click.