Radix Icons - A crisp set of 15×15 icons. Open source.
Android Icons - Androidicons is a professional, handcrafted icon set with 250 icons in 14 different colors and 5 sizes, including an icon font and all sources.
Bjango App Icon Templates - App icon templates for PS, Ai, Sketch and Affinity Designer
Octicons - Your project. GitHub's icons.
MakeAppIcon - MakeAppIcon resizes and optimizes your icon designs into all formats needed for iOS and Android mobile app!
WebHostingHub Glyphs - High quality icons that are easy to use with Bootstrap, other CSS frameworks and in any web projects.