Sticker.Place API - Get stickers for your app
Unixstickers by Sticker Mule - Stickers for fans of unix, software, coding and open source
Acrylic Charms by Sticker Mule - Add some charm to your life.
Polymail - Native email app for email productivity.
Albmoji - Sticker & Emoji pack inspired by Albanian traditions.
GIPHY Stickers for Instagram Stories - Add fun GIF stickers to any photo or video in your story