SAN FRANCISCO: New research has shown that information shared by consumers with health apps is often being sent to companies other than the apps' developers.

The Financial Times commissioned Evidon, a web analytics and privacy group, to look at this area and found that the top 20 health and wellness apps transmitted information to nearly 70 companies, not all of which app users knew about.

Almost half of these were sending data to mobile analytics group Flurry, which offers tools for app developers to measure their audiences and sells ads based on the data it collects. The company stated that the information it tracked was not personally identifiable and was only used in the aggregate.

While many app developers said they did not sell information but used it to improve their own products, others saw the matter differently and had actively sought links with relevant third parties.

MapMyFitness and RunKeeper, for example, have partnered with insurance company Aetna and given users the option to pass on their data.

"Everything is up to the user," said Jason Jacobs, founder and chief executive of RunKeeper. "The data will never be sent anywhere the user does not explicitly permit."

Consumer consent is emerging as a major issue for digital marketers. Recent research from the GSMA, the mobile trade body, found that over 80% of mobile users in Indonesia and Malaysia were concerned about apps that collected personal information without permission.

And the Pew Research Center discovered that similar worries had led to half of US teens avoiding certain apps and a quarter uninstalling an app for the same reason.

But with brands seeking greater targeting opportunities, the pressure on app developers to collect data is increasing. Some analysts predict that health insurance and pharmaceutical companies will buy into the sector as they look for new ways to reach consumers.

The creators of iPeriod, a menstrual cycle tracking app, reported being approached by pharmaceutical companies wanting to target ads at women. Someone who recorded the information in the app that they got headaches just before their period could, for example, be sent an ad for a pain reliever at exactly the right time.

Data sourced from Financial Times; additional content by Warc