The Defense Advanced Research Projects Agency awarded a $5.1 million contract to Kryptowire, for technology that can gather and aggregate smartphone sensor data. The Department of Defense hopes to deploy predictive analytics to track the health of U.S. service members with their phones.

The technology is being developed as part of DARPA's Warfighter Analytics using Smartphones for Health program, designed to provide real-time assessment of physiological signals, remotely monitor health, track medication adherence and detect physical impairment and illness.

"Currently, understanding and assessing the readiness of the warfighter involves medical intervention with the help of advanced equipment, such as electrocardiographs and other specialized medical devices, that are too expensive and cumbersome to employ continuously or without supervision in non-controlled environments," explained DARPA Program Manager Dr. Angelos Keromytis.

"On the other hand, currently 92 percent of adults in the United States own a cell phone, which could be used as the basis for continuous, passive health, and readiness assessment," he said.

Kryptowire, a Department of Homeland Security-funded startup that specializes in mobile app security, plans to develop a secure and context-aware tool to gather data collected from users' smartphones – during both everyday use and during clinical trials – to help improve health outcomes.

The company aims to enable data collection across both iOS and Android smartphones, enabling ease of deployment at scale, data anonymization, secure access control to device data, and transparent data collection, officials said

Beyond just U.S. service members, the aim is to eventually develop this as a consumer-facing technology, offering a new way to detect health problems as early as possible.

"Our strategy is to leverage the full power of mobile to collect health metrics in all patient settings, for continuous monitoring, from clinic to home, and to build the ground truth from all available data, including smartphone sensors, clinical studies, medical examinations etc. for a better-informed, real-time approach to disease detection and biomarker identification," said Kryptowire CEO Angelos Stavrou.

But some observers are raising concerns that continuous monitoring via smartphones' sensors, cameras and microphone, pose big privacy questions.

"If you're activating a microphone on someone's phone, that is going to raise a lot of alarms," Jay Stanley, senior policy analyst with the American Civil Liberties Union, told the Washington Post. "People don't want to feel like someone is listening in on their private life. That's going to have to be subject to tight controls."