The U.S. Food and Drug Administration announced Monday that it will regulate mobile medical applications that could put someone’s life at risk if they malfunction.

The FDA defines a mobile medical app as one used as an accessory to a medical device or that transforms a phone, tablet or other device into a medical device. For example, the FDA will regulate mobile apps that allow you to use your phone as an electrocardiogram to measure the electrical activity of your heart. If the app malfunctions, timely treatment could be delayed.

The FDA will not regulate mobile apps that help people manage but not treat their diseases, access personal or electronic health records, or give medical instructions or guidelines.

For example, the FDA won’t regulate the American Heart Association’s Pocket First Aid & CPR Smartphone app, which provides step-by-step instructions for basic first aid and CPR during a medical emergency.

Although online tools like the American Heart Association’s Heart360 act like other mobile apps, they won’t be regulated because they aren’t distributed through common app sites like Apple iTunes or Google Play. Heart360 will launch a responsive mobile website later this year.

The guidance is needed, given that by 2015, 500 million smartphone users worldwide will be using a healthcare application. By 2018, 1.7 billion smartphone and tablet users are expected to have downloaded mobile health applications, according to the FDA.

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