[Smartphone-the stethoscope of the twenty-first century].
The introduction of the stethoscope into medical diagnostics more than 200 years ago revolutionized medicine and the distribution of roles in the physician-patient relationship. For the first time the physician was in the position to perceive body and life phenomena in the patient, which remained hidden even to the patient. That was the beginning of a dependency relationship of the patient in the recognition and assessment of symptom-associated normal deviations, which is still continuing today. The continuous recording of health-relevant data by the patient, heralds a reversal of this data hegemony. Thereby, step by step patients are reclaiming their role as the subject in the distribution of roles between physician and patient.