The present invention concerns the field of communication between a server and target devices not connected to a communications network. The context of use is typically the management of a fleet of devices by an operator.A generic mobile application is described, for relaying messages between these non-connected devices and a management server. This application is intended to operate on a mobile terminal hold by a person moving close to the equipment. The terminal and the equipment are provided with point to point communication means. The terminal communicates with the management server when it is located within range of a communication network. The application makes it possible to store and resend the messages between the moment when the terminal is connected to the communications network and the moment when the terminal is connected to the equipment.