Apple has also hired hardware experts Nancy Dougherty, formerly of wearable sensor company Sano Intelligence, and Todd Whitehurst, vice president of product at Senseonics, a glucose monitoring product, according to their LinkedIn profiles.
And most recently, Divya Nag, founder of StartX Med, a Stanford-affiliated startup accelerator, joined an Apple research and development team two weeks ago to focus on an unspecified healthcare product, two people familiar with the matter say. Nag did not respond to requests for comment.
Attempts to contact the people on LinkedIn were not successful, except for Ferdosi, who declined to comment. Sano and Vital Connect declined to comment, Masimo and Cercacor confirmed the departures, Senseonics did not return an email requesting comment and O2 MedTech could not be reached.
'Just buying people'
Singularity University's Daniel Kraft, who chairs the FutureMed program that explores developing technologies and their potential in biomedicine, said the first version of the iWatch might track blood pressure and heart rate, among other vitals.
Eventually he expects Apple to release a device that could continuously monitor glucose levels without requiring a blood draw.
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"Some of the talent (Apple recruited) has access to deep wells of trade secrets and information," said Joe Kiani, chief executive officer of medical device firm Masimo Corp, who lost his chief medical officer to Apple in mid-2013.
Kiani said that Apple was offering sizeable salaries with little indication of what researchers would be doing. "They are just buying people," he said. "I just hope Apple is not doing what we're doing."
Apple may face regulatory hurdles if it aims for devices which do more than monitor fitness. In January, the New York Times reported that Apple executives, including O'Reilly, met with senior officials at the Food and Drug Administration, including Bakul Patel, who drafted the FDA's final guidance for mobile health.
In fall of 2013, the FDA announced that it would focus on regulating applications that attempt to turn a smartphone into a medical device, or that are intended to be used as an accessory to a regulated medical device. That might include apps and attachments to measure lung function or analyze urine, for instance, but not devices such as Nike's FuelBand, which tracks your steps but does not offer medical recommendations.
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Apple also has witnessed rivals trying, and failing, to produce devices that reach a mass market. Samsung's Galaxy Gear smartwatch was panned by critics and consumer reviews have been tepid at best.
A report from Endeavour Partners found that one-third of American consumers who have owned a wearable ditched it within six months. Key challenges include battery life, style, usefulness, and medical relevance, it said. And this month, Nike confirmed to Re/code that it had laid off some of its FuelBand team.
Meanwhile, Google is taking a different approach. In March, it pre-empted Apple by unveiling Android Wear, a version of its Android software tailored for wearable devices. Like Apple, it's shown interest in medical technology: it is exploring contact lenses that can monitor glucose levels in tears.