MongooseIM platform
The massively-scalable XMPPJabber mobile messaging platform, for mobile and web, by Erlang Solutions.
Skygear Chat is an open-source chat backend that provides Chat SDKs (iOS, Android and JS) and messaging APIs for developers to build or add chat feature quick. .
Key Features in SDKs:1. Fullfeatured crossplatform messaging2. Create direct conversations and group chats3. Real time send message & receive message4. Image and media files support5. Unread conversations/messages count6. Manage users in chat groups7. Typing indicators and recipient status8. Push notifications9. Chat history10. Devices / user online presence indicator
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chat-clients messaging-client chat-servers messaging-sdk push-notification-service pubsub mobile-development-api