Abstract: The systems and methods of out of band application synchronization across devices disclosed herein include a companion application running on a secondary device, such as a mobile device. An out-of-band file containing program event markers is transmitted to a set top box. These program event markers may be used to link the program watched on the STB or the mobile device. Upon reaching the position indicated by the out-of-band file, the payload may be sent out by the STB to an application on a secondary device. The secondary device running the companion application receives the payload and triggers an action to fetch the associated metadata from the server. The companion application may include related content or advertisements, and communicate with a social network or the user's network to communicate at the same time with other customers watching the same program.