Healthcare providers looking to engage patients will find a key enabling—and potentially disruptive—tool in their back pockets: the smartphone.  Writing in the Saturday edition of the Wall Street Journal, cardiologist Eric Topol, MD, reviews a growing portfolio of powerful new applications and devices that can diagnose an ear infection, monitor mental health, track heart rhythms and even generate x-rays.

“I thought I’d seen it all in my decades-long practice as a cardiologist, but recently, for the first time, I had an ECG emailed to me by a patient, with the subject line, 'I’m in atrial fib, now what do I do?' I immediately knew that the world had changed. The patient’s phone hadn’t just recorded the data; it had interpreted it,” he writes.

Acknowledging that patient-date safety issues have yet to be addressed, Topol writes that there are apps for diagnosing skin rashes and recommending next steps and for securing video consultations with a physician day and night ($30–$40). Deloitte estimates that one in six physician visits in 2014 were virtual. He forecasts bigger changes ahead, like generating your own personal medical data using wireless wearable sensors and a smartphone, including the measurement of blood-oxygen and glucose levels, blood pressure, heart rhythm and other vital signs, raising the potential to replace hospital beds with our own bedrooms.

Of great relevance to radiology: Most medical imaging devices are undergoing miniaturization, beginning with ultrasound and Topol says hand-held MRI is not far behind. UCLA has devised a smartphone-sized device that can generate x-rays, he reports.

“Just as the printing press democratized information, the medicalized smartphone will democratize health care,” he concludes. “Anywhere you can get a mobile signal, you’ll have new ways to practice data-driven medicine. Patients won’t just be empowered; they’ll be emancipated.”