Apple has banned developers who are building apps using the HealthKit feature in iOS 8 from sharing the data with ad networks.
The rules were stated in an update to the developer program license agreement, saying developers: "must not sell an end-user's health information collected through the HealthKit API to advertising platforms, data brokers or information resellers."
The policy continued: "Your application must not access the HealthKit APIs unless it is primarily designed to provide health and/or fitness services, and this usage is clearly evident in your marketing text and user interface. You and your application may not use the HealthKit APIs, or any information obtained through the HealthKit APIs, for any purpose other than providing health and/or fitness services in connection with your application (e.g., not for serving advertising)."
However, the information can be shared with third parties for medical research, providing the developers have the consent from the user to do so.
Apple's HealthKit API will allow developers to build a range of apps designed to monitor an individual's vital signs including blood pressure, heart rate, sleep patterns, calories burnt, blood sugar and cholesterol using connected wearables.
This data can then be shared with doctors and other health professionals or maybe even insurance companies to alert them to any changes in the individual's health status.
The issue of private health information possibly becoming public has also hit the upcoming release of Apple's iWatch. Research done by Cass Business School's Professor Andre Spicer looked at the ethical issues that could arise.
"The public is becoming more concerned about who owns and controls the stream of personal data about things like health produced by wearable technology," he said. "It seems strange we force prisoners to wear tracking technology, but trendy smart watch users pay for the privilege.
"One big ethical issue users did not consider is how these devices will be used to track and collect intimate data about their everyday lives," Spicer continues. "Most smart watches have life-logging technologies which collect data about bodily rhythms. These could be used as a potential surveillance device.
"It could also see technology companies selling our most private health information to a whole range of parties such as insurance agencies."
A number of health-related organisations in the US have said they will be developing apps to work with the API, including health centres and the US Food and Drug Administration, although it remains to be seen how companies in the UK will use such apps.
Apple is expected to announce the iPhone 6 and iWatch with built-in health sensors next week. The iPhone 6 is rumoured to feature a 4.7in screen and will run on iOS 8.
