GIPHY for iMessage - The easiest way to share all the GIFs in all your txts
Acrylic Charms by Sticker Mule - Add some charm to your life.
MojiLaLa Unlimited for iMessage - 32,000 original stickers by 450+ artists all over the world.
Sticker.Place API - Get stickers for your app
Doll Up Stickers - Dress up your messages.
Albmoji - Sticker & Emoji pack inspired by Albanian traditions.