A team of biomedical engineers have developed a smartphone app that can track vital signs, such as heart rate, through the use of built-in mobile phone cameras.

Although the app isn’t scheduled to hit markets until the end of the year, Ki Chon, professor and head of biomedical engineering at Worcester Polytechnic Institute, located in Massachusetts, said it will be marketed mostly to medical professionals. He said apps related to diagnosing and detecting medical issues have to be approved by the FDA in order to be marketed to general audiences.

“The FDA would have to iron all these things out, and the mobile health market is such a fast–changing technology,” Chon said. “I don’t think they really have set the guidelines for this kind of technology yet, which is why we’re not thinking about selling it in an app store.”

The app can measure heart rate, heart rhythm, respiration rate and blood oxygen saturation by using camera and flashlight technology in iPhones and Android phones to scan the user’s finger. Chon said phone flashlights have red-blue-green color models, and the green color wavelength can be used to reflect oscillations that detect heart rate. Then, algorithms developed by the research team can be used to turn that information into other vital statistics related to body function.

Chon said the technology would be helpful in detecting atrial fibrillation, which is the most common form of cardiac arrhythmia (abnormal heart rhythms). He said patients with atrial fibrillation often don’t show symptoms, making it hard to diagnose. He hopes this new app will help make it easier for patients and doctors to detect this disease.

“The more you monitor, the chances of finding these intermittent problems increases, and that’s the idea with this kind of phone,” Chon said.

The research team, which also included Yitzhak Mendelson, associate professor of biomedical engineering at WPI; Domhnull Granquist-Fraser, also an associate professor of biomedical engineering at WPI; and Christopher Scully, a WPI doctoral student, tested the accuracy of the app by strapping into standard medical equipment to monitor vital signs, while simultaneously using the new app to test. Chon said the results showed the app to be just as accurate as current medical equipment.

“Our team wore [traditional medical equipment] at the same time we tested the mobile phone, and there was a good correlation between the results,” he said. “We’re doing more extensive studies at the moment to further test accuracy.”

The phone would be marketed to iPhone and eventually iPads, and not Android devices. Chon said this is because with iPhones, there is less chance of people hacking and copying apps.

“Our invention was largely tested in a android market—but it’s optimal for iPhones,” he said.

The research team is funded by the Office of Naval Research, an agency within the Department of Defense. According to Chon, they are also applying for grants from National Institutes of Health, a U.S. Department of Health and Human Services organization that funds medical research.