Apple has tightened privacy rules for developers collecting data from its new health app as it prepares to launch a range of new products – which may include a wearable tech device.

In June this year, the technology giant unveiled plans for its HealthKit platform to capture biometric data for vitals such as blood pressure and heart rate, as well as statistics for diet and exercise.

HealthKit, part of Apple’s new iOS 8 operating system, will initially store around 60 different types of health data, such as blood pressure and glucose levels.

Apple’s ‘Health’ app will display the data gathered by HealthKit, and will allow users to share information with their doctor if they choose.

To address privacy concerns about how the data is gathered and shared, Apple has released new rules for developers of apps that want to take advantage of HealthKit.

The guidelines state that while developers can collect the data that Apple will hold, they “may not use user data gathered from the HealthKit Application Programme Interfaces for advertising or other use-based data mining purposes other than improving health, medical, and fitness management, or for the purpose of medical research”.

"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)."

Any apps that share user data acquired via HealthKit API with third parties for medical research purposes must first get user consent or they will be rejected.

The security of Apple’s products and systems has come under heightened scrutiny in recent weeks, after a hacker gained access to the iCloud accounts of a number of celebrities and posted naked pictures online.

Apple has identified the cause of the breach as "a very targeted attack on user names, passwords, and security questions", denying its systems were breached.

However, Apple chief executive Tim Cook told the Wall Street Journal the company will strengthen the security of the iCloud service by alerting users when someone tries to change an account password or restore their iCloud data to a new device.

The furore has threatened to overshadow Apple’s upcoming launch event today, at which it is expected to unveil a number of new devices.

One of those is expected to be a wearable technology device, or ‘iWatch’, with a strong focus on health and fitness.

The iWatch has been rumoured to include more than ten different sensors to track movement, vital signs and footsteps, while also making use of the HealthKit platform.

Apple has also announced partnerships with a number of healthcare organisations and suppliers, including American electronic patient record supplier Epic and non-profit US medical practice the Mayo Group.

Update: Apple unveiled its Apple Watch on 9 September, with a strong focus on health and fitness monitoring, The smartwatch includes a custom heart rate sensor and an accelerometer to measure total body movement. It also uses the iPhone’s GPS and Wi-Fi to track how far a user has moved, but at the launch there was little discussion on the links with the healthcare sector.

An ‘Activity’ app on the watch will display daily activity graphics, with information on how many calories have been burned, how many minutes of “brisk activity” have been completed, and how often the user has stood up during the day.

A separate ‘Workout’ app for cardio sessions will show real-time information on time, distance, calories and pace, allowing users to set goals for each workout and using the information it collects to suggest personalised daily fitness goals. You can have a look at the watch here.

Read more about the potential impact of the launch on health and technology market in the Insight: 'Apple bites into wearables'.