A mobile phone-based telemonitoring system for long-term psoriasis therapy is described, intended to increase patients' compliance by optimizing the patient-physician communication. Patients themselves can acquire health parameters and take photos of their psoriasis lesions. The data are sent to a monitoring centre, where they are provided to the patients' physician who returns a feed-back message. The system is currently tested in a study with 20 patients. Preliminary results prove the feasibility and usabililty of such a system and indicate that it is useful for optimizing psoriasis-therapy.