There are provided systems and methods for shared application interface data through a device-to-device communication session. A user may utilize a device to engage in an electronic communication session with another user, such as a shared messaging or video chat session. During the session, the user may utilize another application on the same device to perform separate application data processing, such as accessing a website or an online marketplace that may include interface output data. The user may activate a plug-in or add-on that may allow application data sharing for current application data in the separate application during the communication session. The device may determine the present application data, such as a displayable instance of the current interface data, and may transmit the data to the other user's device through the communication session. Further, the plug-in may allow for split transaction and data processing.