Webxdc is a new way to create and share web apps in messenger chat groups. Anyone can build HTML5 apps, package it as a .xdc file, and drop it in a chat to share with friends. Once shared, chat participants can simply click "Start" to run the app and interact with each other through the app.

Webxdc apps can only send and receive messages in the chat via the messenger's JavaScript API. Thus they automatically get end-to-end encryption and peer discovery for free.

Webxdc is specified through its file format for packaging as a .xdc file, JavaScript API for developing web apps, and Messenger implementation for running and sharing Webxdc apps in chats. Webxdc is supported by and evolving with the Delta Chat e-mail messenger, which serves as the default reference.

See the webxdc GitHub organization for further developments and feel free to post questions or suggestions in the Webxdc support forum.