Systems and methods cross device application discovery and/or control. Cross device application discovery and/or control can provide for simple detection and activation of applications on remote devices. Cross device application discovery and/or control can provide for the control of remote applications in a master and slave configuration. Responsive to an activation message, an application can execute a task in an application, the task being displayed on a target device. Responsive to an activation message, an application can execute a task in an application on a target device, a task context data for the task being streamed to the source device for presentation on a display. Cross device application discovery and/or control can be enabled on a single operating system, or across a plurality of operating systems.