The HealthKit app that comes standard on the iPhone previously came under criticism for making it possible to track all the minutiae of what your body is doing—except for menstruation. Now Apple has fixed that problem, adding menstrual tracking, cervical mucus, ovulation testing, and other lady things. Oh yeah, and "sexual activity"—you can track that, too.
There was a minor flurry of headlines about how Apple is now tracking your sex life, but while the app does automatically track, say, how much walking you do, there's no way for it to know how much sex you're having. As these screenshots show, there's only two things you enter to record "sexual activity": whether it happened and whether you used protection.
So if you, say, had intercourse and used a condom, you're set. But what if you're on the pill but not using a condom? What if you had oral but not intercourse? Does masturbation count? What if you messed around a little with your partner but no one orgasmed? Does it have to have penetration to count? If so, what about lesbians? There's a whole world of sex outside of yes/no and protection/no protection.
These questions about what is and isn't sex existed long before the iPhone asked you to start counting your sexual widgets. And unless you're looking for in-app alternatives to carving notches in your bedpost, it's hard to imagine that this function on HealthKit has any use whatsoever. Still, it isn't every day that a standard, boring app on the iPhone inadvertently triggers a bunch of hard-to-answer philosophical inquiries about the nature of sex.