(Reuters) - CVS Health Corp’s health insurer Aetna on Tuesday said it is working with Apple Inc on a new health app for Apple Watches that uses an individual’s medical history to set personalized health goals.

FILE PHOTO: A demonstration of the newly released Apple Watch Series 4 is seen following the product launch event at the Steve Jobs Theater in Cupertino, California, U.S. September 12, 2018. REUTERS/Stephen Lam -/File Photo

Called “Attain,” the Apple Watch app will reward Aetna customers for meeting activity goals and fulfilling recommended tasks, such as getting vaccinations or refilling medications, with a subsidy toward the cost of an Apple Watch or gift cards for U.S. retailers.

Several insurers have offered such subsidies for using wearable devices to meet generic activity goals such as a number of steps in the past. But what is new and significant about the Attain app is the use of personal health data held by Aetna to provide customized goals and recommendations.

That health history data is tightly regulated by the U.S. government, and Apple and Aetna had to enter into what is known as a business associate agreement in order for Aetna to share it with the Apple.

Access to regulated data is necessary for some of the functions of the app, such as recommending age-appropriate exercise or a lower-cost option for scheduled lab tests or MRI imaging tests. Aetna said the program is voluntary and that data gathered will not be used for premium pricing or coverage decisions.

“We understand that you don’t need to be a personal trainer or work out several hours a day to be healthier,” Alan Lotvin, executive vice president for transformation at CVS Health, said in a statement.

For Apple, the Aetna partnership continues a push into regulated areas as the company dives further into health features with its wearable device launched in 2014.

Last fall, Apple announced a watch with the ability to take an electrocardiogram, an electrical measure of heart activity that can detect heart problems. The feature required clearance from the U.S. Food and Drug Administration.

Aetna users can opt to share their information anonymously with Apple. Apple will use techniques such as machine learning to fine tune the app, such as detecting the users are more likely to follow up on tasks if they notified midday rather than in the morning.

“As we learn over time, the goal is to make more customized recommendations that will help members accomplish their goals and live healthier lives,” Jeff Williams, Apple’s chief operating officer, said in a statement.