In example implementations, a method for starting a companion application on a mobile endpoint device and an apparatus for performing the same is provided. The method is performed by a processor of the mobile endpoint device. The method includes detecting that a distance between the mobile endpoint device and a main computer is less than a target distance. The distance is based on a signal strength of a wireless communication signal between the mobile endpoint device and the main computer. An application that is being executed on the main computer is detected. A companion application is started on the mobile endpoint device that is associated with the application.