science of us

I Cherish My Period Tracker

Clara might have also been a fan. Photo: Bettmann/Getty Images

I’ve been a devoted user of the period-tracking app Clue since February 2014. I’m attached to the ritual of entering my tedious little facts as if they might somehow unlock a profound personal insight; it feels like having a dull but reassuring diary, a tiny adviser, proof of existence.

I’ve enjoyed retroactively seeing where my cycles lined up with the waxing and waning of the moon (for which I also have an app), and where I was in my cycle when I met certain people, did certain things, felt certain ways. Not that they always (or ever) align the way I imagine they might, but it’s been fun/interesting, if not hugely scientific, to have the data available — it feels a little like having a long-term personal fingerprint. The app and others like it, of course, also purport to track ovulation and fertility.

I like the Clue site, too, which radiates sturdy, gentle authority, and I appreciate that the company was co-founded by a female entrepreneur (the Danish-born, Berlin-based CEO Ida Tin), and that their team now includes doctors, scientists, and staff from around the world. I love Clue. It was me, in the bedroom, with the smartphone. (A Clue joke. Clue the game.)

I even relish entering gross information into my defenseless little Clue, and I like the idea that years of my mundane observations might somehow benefit “science.” In fact I was sort of pathetically thrilled a couple months ago when I realized that this whole time they’d had a way for me to enter digestive regularity into Clue. It aligns with cycles; how had I not realized? Well, it sometimes does.

Anyway, in a story for Vox about the dark side of period-tracking apps, writer Kaitlyn Tiffany outlines the ways that the apps are “not built for women,” pointing out that many of the apps are infantilizing and poorly designed, that it’s not always clear where the data we enter is going, and that none of the most popular apps allow for the inclusion of atypical events, such as pregnancy or abortion, which can skew cycle averages and affect overall data accuracy. (As one woman she spoke with said, her tracker logged her pregnancy as “a several-hundred-day menstrual cycle.”)

“But what about Clue?!” I thought, as I read about the various apps’ shortcomings, as if it were a friend of mine. Tiffany acknowledges that Clue is something of an outlier and a beacon in an otherwise murky field, describing the app as “anti-fluff,” “science-backed and science-obsessed,” and with “a robust, doctor-sourced blog.” (Her main bone to pick appears to be with Glow, the No. 1 period-tracking app, which has 15 million users to Clue’s 10 million. They are the two biggest.)

Tiffany ultimately makes the switch from Glow to Clue, although she scandalized me by also taking issue with an aspect of Clue that I’ve always found sweet, which is that when you enter in any data at all, a little notification momentarily says “Clue is getting smarter …” (After which it says, “We’ve updated your predictions.”)

Her response: “Gross?” And: “It’s all so undignified.”

I almost gasped. Fortunately there is a field in the Clue app that allows me to report feelings of internet-driven menstrual outrage. Just kidding, for now.

I Cherish My Period Tracker