Inexpensive and easy-to-use technologies are transferring the do-it-yourself principle to the healthcare sector too. Self-tracking is a new level in the sense of self, whereby people focus on the quantification of their own activities and performance data. A technological basis is formed by biofeedback sensors in wearables and they measure physical functions like heartbeat, skin temperature, muscle tension and brain waves. This makes emotional and somatic conditions more visible and they are used to optimize lifestyle and health. The independent control, diagnosis and treatment of complaints is becoming ever more important. At the same time, the diagnosis devices required for this are getting smaller, while wearable labs are now no bigger than computer chips (“lab-on-a-chip”).