Smartphones and wearable technology are changing medicine rapidly. In particular, sophisticated smartphone cameras have opened up a world of convenient innovations for patients, from the ability to do virtual check-ins with their doctor to monitoring vitals from the comfort of their home.

One of the latest camera-based tools is HemaApp, developed by electrical engineers and computer scientists at the University of Washington (UW). The app helps screen patients for anemia, a condition with which there is a shortage of red blood cells. Patients put their finger on the camera lens, and the light from the flash illuminates their blood. HemaApp then analyzes the color of their blood to estimate hemoglobin concentrations.

In an initial trial of 31 people, conducted last year and detailed in a paper, the app correctly identified patients with low hemoglobin levels 79 percent of the time with just the phone camera; when another light source was added, that accuracy went up to 86 percent. The app is still being evaluated; researchers intend to test it nationally and internationally, collecting more data and working on improving accuracy.

For leukemia or surgical patients who need frequent checks of their hemoglobin level, HemaApp would be less invasive than repeated blood draws, says study coauthor Terry Gernsheimer, a UW Medicine and Seattle Cancer Care Alliance (SCCA) hematologist and transfusion medicine specialist. And since anemia is one of the most common problems affecting adults and children around the world, HemaApp could be especially useful in places with limited resources, says Doug Hawkins, another co-author of the study and a pediatric cancer care specialist at Seattle Children’s Hospital, SCCA and UW Medicine. 

HemaApp uses technology that was first developed by the UW’s UbiComp lab for another mobile app, BiliCam, which uses a smartphone’s camera and flash to check newborns’ blood for jaundice. That app was recently tested in a nationwide clinical trial of 500 newborns.