This paper presents a design of a telehealth mobile system based on the commercial GSM network. The system is composed by three blocks: data acquisition system, data sending and receiving and data visualization. In the data acquisition block several devices for sensing vital parameters were designed constituting a Body Sensor Network, BSN. Temperature, Heart Rate, Respiratory Rate and Blood Pressure were sensed. Some mobile applications for both cell phones and smartphones were developed in order to acquire other clinical data. A system under the GSM network was programmed for sending the information. This constitutes the second block. The connectivity capabilities of the Cell phones and smartphones were used for sending the forms. For sending the vital signs acquired a commercial hardware was implemented. A web application was developed in the third block. This application allows the remote visualization of the data. The system proposed provides an affordable, efficient and flexible platform for telemonitoring relevant clinical parameters from patients.