Smartphones have transformed how we listen to music, chat with friends, read the news, pay our bills, and more. Now they’re poised to revolutionize health care.

Maybe you already use your phone to count your steps or remind you to take your meds. But just wait: Apps and plug-in accessories are turning the basic smartphone into what some have likened to a “doctor in a pocket” — a single device that one day could perform basic lab tests and reliably diagnose health problems ranging from simple infections to cancer.

“The smartphone is becoming the central hub for medicine,” Dr. Eric Topol, director of the Scripps Translational Science Institute in La Jolla, California and a noted expert on digital medicine, told the Financial Times. “Most routine medical tests are about to be smartphone-mediated.”

Cardiologist Dr. Sarah Timmapuri looks at data on a smartphone synchronized to a new Fitbit Surge worn by patient Gary Wilhelm, 51, during an examination, in Hackensack, New Jersey in 2015. Mel Evans / AP file

Many of the new apps make use of a phone’s microphone or camera. Others rely on small attachments, typically costing less than $100, Topol told NBC News MACH.

Some attachments act like tiny EKG machines to let your phone monitor your heart’s activity — you simply place your fingers on a credit card-sized sensor for 30 seconds and check your phone to see if your heart rhythm is normal.

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Worried that your kid might have an ear infection? You can plug an otoscope into your phone and then take a video of the eardrum and send it to your pediatrician.

More ambitious apps

Even more ambitious medical apps are in the works. Stanford researchers, for example, recently designed a computer algorithm that purportedly can tell whether a skin lesion is cancerous just as accurately as a dermatologist. They anticipate adapting the technology for smartphones.

At the University of Washington, researchers created an app to screen for pancreatic cancer. It works with a light-blocking phone enclosure that lets you take a perfectly exposed selfie; the app’s algorithm checks the whites of your eyes for subtle signs of jaundice, which can be evidence of malignancies of the pancreas and other diseases.

Eventually, apps might help people with diabetes control their insulin levels. Scientists recently implanted capsules of insulin-making cells under the skin of diabetic mice, and successfully switched them on via an app.

Tapping into data

Topol is convinced that doctors will want to tap into the abundant health data captured by their patients’ apps as a way to enhance the care they provide. “It democratizes medicine so people…are generating the data, they’re looking at the interpretation, they’re helping to drive their care,” he says.

Experts caution that many medical apps are in early stages of development and thus may be of dubious reliability. A blood pressure app, for example came under fire last year for giving inaccurate readings.

Medical apps raise other concerns, including privacy and whether hackers will be able to get access to app users’ medical information.

Given such concerns, Alex Mariakakis, one of the University of Washington researchers, says, “We’d never want to use this stuff to replace doctors.”

Then again, Andre Esteva, one of the Stanford researchers, predicts that in a few years “anybody who has a mobile phone can get better access to care than they currently have.”

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