 Based on previous research on the bio-optics of jaundiced newborn skin, a prototype of a smartphone application has been developed. This prototype will be evaluated in a clinical trial at St.Olav Hospital, Trondheim, Norway. A smartphone will be used to take picture of the skin of the newborn, and by using an algorithm an estimate of the bilirubin concentration is made. The results from these estimates will be compared to the bilirubin levels measured in standard blood samples, as well as the results from ordinary transcutaneous measurement devices. 