Tim Cook, chief executive officer of Apple Inc., waves before speaking during the Apple World Wide Developers Conference (WWDC) in San Francisco, California, U.S., on Monday, June 8, 2015. Photographer: David Paul Morris/Bloomberg

Cue Siri to play Marvin Gaye's "Let's Get it On."

New features on Apple's pre-installed "Health" app will allow users to track their sexual activity, namely whether or not they used protection and the time of day they had sex.

The new Health app, which already tracks other health information like fitness and nutrition data, will be available on iOS 9, which is set to come out later this year, and will also include the ability to track other reproductive health metrics like menstruation and ovulation cycles.

And all that is great, some users say -- Apple notoriously ignored women's health issues as it developed previous versions of Health -- but also not so great, others say, since tracking how often people do the deed is perhaps a little too personal.

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"Really think it through. Why do I need a computer to figure out this part of my life?" said Teresa Schoch, associate director of Berkeley Research Group.

You don't,  Schoch thinks, especially if the data you enter ends up on some kind of cloud or external server.

You can choose to store your data solely on your device without backing it up to the cloud. But Apple also let's you choose to share your data with your doctor or anonymously with researchers.

Apple is also set to release "HealthKit," which will pool data entered into various health and fitness apps. For example, if you use an app that tracks blood pressure and another that tracks caloric intake, those apps could share the information they gather with HealthKit to provide a comprehensive overview of your health data.

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And that, in a Utopian world where all data is safe all the time and nothing bad ever happens on the Web, sounds like a fantastic way to track your health.

"It just might be the beginning of a health revolution," Apple's Website reads.

Or it could be a great way to put personal information at risk and provide hackers nuanced and specific information.

"Data about reproductive health is very sensitive, but there are situations where maybe you want someone to know that," said Harlan Yu, principal at Upturn, a technology consulting firm. "You might want your doctor or researchers to know that. But in other situations you might not want drug companies or insurance companies to have that information."

Think about this: Harvard professor Latanya Sweeney found in a 2000 study that 87 percent of Americans were uniquely identifiable based on their gender, birth date and zip code. Oh, and Sweeney found all that information using Census data that at the time was 10 years old.

It was found that 87% (216 million of 248 million) of the population in the United States had reported characteristics that likely made them unique based only on (5-digit ZIP, gender, date of birth). About half of the U.S. population (132 million of 248 million or 53%) are likely to be uniquely identified by only (place, gender, date of birth), where place is basically the city, town, or municipality in which the person resides. And even at the county level, (county, gender, date of birth) are likely to uniquely identify 18% of the U.S. population. In general, few characteristics are needed to uniquely identify a person.

So now, imagine what nuanced health information could say, even if it's collected in bulk or anonymously and even if it's not obtained nefariously, Schoch says.

"They can pinpoint you if they wanted to," she said.

That doesn't mean health data collection is inherently dangerous, though. Collection of reproductive health data feels more creepy, but it can still be innocuous.

"The way I look at this stuff is I look at harm," said University of Washington law professor Ryan Calo, who specializes in Internet privacy. "Could this information be used in a way that could disadvantage you?"

That's a question to answer before using an app to track your bedroom behavior.