Described herein are techniques related to sharing applications between two client devices assigned to the same user. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope and meaning of the claims. A shared-application tool allows a user to request to use an application that is installed on host computing device on a client computing device. The request to use the application is made to a directory service using a message-exchanging protocol. The application is run on the host computing device and provided to the client computing device using a peer-to-peer communication protocol.