Snapchat - Real-time picture chatting
MessMoji - Emoji stickers for iMessages
Element.io - Secure messaging app with strong end-to-end encryption, advanced group chat privacy settings, secure video calls for teams, encrypted communication using Matrix open network. Riot.im is now Element.
Dango - Use emoji, stickers & gifs faster 😄 💬
StealthChat - StealthChat is Encrypted, Private, Secure Calls and Chats on Android and Apple iOS
Neural Network Generated Illustrations - Create a personalized sticker pack in Allo