PERIOD. in How About Mom: 'I came to learn, not to close pop-ups'

On 2 August 2026, Dutch parenting platform How About Mom published an interview with our founder Lisa Volkers in its women supporting women series, written by Annemarie Maalderink. The series profiles female founders building products specifically for women and mothers.

It started with irritation

The cycle app Lisa used kept steering her towards a possible pregnancy, while that was not the phase of life she was in at all. When she talked about it with friends, they all recognised it. "There are plenty of cycle apps out there. I never expected that so many other girls and women shared this frustration", she says in the piece.

Together with her partner she built PERIOD. as an alternative. What started as a simple, privacy-friendly app for herself and her friends grew to thousands of users within weeks.

Why wanting a baby is valuable information

Researching the category, Lisa found that information about a possible desire to have children is commercially valuable. "That's kind of the gold", she says. "Once it's known that you want to get pregnant, they can approach you with everything baby-related. Women spend a lot of money in that period."

That, she argues, is why some apps ask not only when your period started, but also about sex, symptoms and possible pregnancy. The most painful example: women who kept seeing ads for baby clothes and prams after a miscarriage. "You're grieving and still being confronted with ads for baby products. I found that very painful to read."

PERIOD. works differently: we only ask what's needed to track your cycle, you can enter a different name so your account isn't tied to your identity, and your data doesn't go to advertisers. The details are in our privacy statement.

No pink, no rainbows, no pop-ups

The design had to be different too. "Everything was pink, with rainbows and huge amounts of information. I came to learn something, but mostly got overwhelmed by pop-ups and things I had to close", Lisa says. In PERIOD. you decide what you see: if you only want to track your period, you don't get unsolicited pregnancy content, and you're not constantly pushed towards the paid version.

"I'm not crazy, I'm in this phase"

By logging her symptoms, Lisa discovered that her headaches and mood swings kept returning at the same point in her cycle. "In 29 years I had never linked it to my period, even though it happened every month. Now you know: I'm not crazy, I'm in this phase of my cycle."

That pattern recognition is built into the app: log your symptoms and see what recurs per phase.

Free stays free

The core version of PERIOD. is free and should stay that way, younger girls in particular don't always have money for a subscription, while they benefit most from understanding their bodies. When users asked whether they could donate, Lisa chose to offer something extra instead: PERIOD. plus at €3.99 a month.

There's also PERIOD. at work, which lets employers give their female employees access to the plus version. Every employee gets her own code; the employer never sees personal data.

What's next

In future, Lisa wants to add features around fertility, perimenopause and menopause, deliberately taking her time. PERIOD. stays a helpful lifestyle tool and won't become a medical app. "I don't want to sell hot air. Everything we add has to genuinely help women and be well-founded."

FAQ

Does PERIOD. share my cycle data with advertisers?

No. We don't sell or share your data with advertisers, and we only ask for what's needed to track your cycle. You can also enter a different name so your account isn't tied to your identity.

Is PERIOD. free?

Yes, the core version is free and stays free. PERIOD. plus costs €3.99 a month and adds extra features, such as more personalisation and reports for your doctor.

Is PERIOD. a medical app?

No. PERIOD. is a lifestyle tool that helps you recognise patterns in your cycle. For persistent or severe symptoms, see your doctor.

Read the piece

The full interview (in Dutch) is on howaboutmom.nl. More press about PERIOD. is on our press page.

Want to try it? Download PERIOD. on the App Store or Play Store.