Flo tracks her.
Yuni tells you what to do.

The 30-second summary

Flo is the world's biggest period-tracking app. About 380 million people use it. It is genuinely good at what it does — predicts cycles, logs symptoms, gives medical-grade information. But it was built for the person menstruating, not for her partner.

Yuni is built for the partner. It does not replace Flo. It explains what each week of her cycle means for him: what she may feel, when not to start a hard conversation, what helps on the bad days, what to do during the good days. One app per person, both quietly running in the background of the relationship.

	Flo	Yuni
Built for	The person tracking her cycle	Her partner — boyfriend, husband, fiancé
Account required	Yes (email)	No
Cloud sync	Yes (cycle data on Flo's servers)	No — stays on your phone
Daily guidance for the partner	None — partner mode shows her data	5 daily modes (Care · Energy · Connect · Calm · PMS)
"What to say" / "What not to say" scripts	No	Yes — phase-aware
Medical content	Reviewed by ~80 medical experts; clinically detailed	Conversational; partner-relational, not medical
Pricing	Free with ads · Premium £39.99/yr	Free trial · Weekly £4.99 · Annual £79.99
Pairing with partner	"Partner mode" — she shares her predicted cycle with him	Pair link — her data on her phone, his guidance on his phone, no central server

When Flo is the right choice

If she wants to track her cycle, log symptoms, predict her next period, manage contraception or family planning, or share data with a doctor — Flo is hard to beat. The medical content is genuinely well-reviewed. The cycle prediction model is mature. If she's already used to it, switching her off Flo is unnecessary friction.

Flo's "partner mode" is a feature in the same app — you create an account, she shares her cycle predictions with you, you see what phase she's in. It works. It is also half the loop: it tells you the date, but not what to do with it.

When Yuni is the right choice

If you have ever stood in the kitchen at 8pm wondering whether to bring up the rent conversation tonight or sit on it for three days, Yuni is for you. The app's job is small and specific: every morning, tell you what week she's in, what she may feel, and what helps. Then get out of the way.

The privacy model matters here. Yuni doesn't ask for an account because the partner-support category is one where men quietly download an app, use it for a month, and never tell anyone. We optimised for that user. Her cycle data — when you pair — never leaves the two phones.

Yuni's other moat is the script library. "What not to say to her on her period." "How to apologise when you don't know what you did." "The 20-minute pre-period conflict protocol." These exist because they're what partners actually search for at 11pm. Flo doesn't write content for that audience.

The simple verdict

The real-world setup is usually Flo on her phone, Yuni on his. They don't compete — they fill the gap each other leaves.

How they work together

The most common Yuni user has a partner who tracks her cycle in Flo or Apple Health. They pair via Yuni's link (her data, no third-party sync), and Yuni reads her phase from the paired source on her phone, then renders it as a daily nudge on his.

If she doesn't track at all, that's fine too — Yuni works from a single estimated cycle date. Less precise, still useful.

Quick answers

Is Yuni a Flo competitor?

No. We never recommend switching her off Flo. Different audiences, different jobs.

Does Yuni replace partner mode in Flo?

For most partners, yes — and most prefer it. Flo's partner mode shows you the same data she sees, in her UI. Yuni reframes the same data as "what to do today." The unit of value is different.

Do you need an Apple Watch?

No. Yuni runs on iPhone. iOS 17+. Apple Watch and Live Activities are coming but optional.

What does it cost?

Free trial. Weekly £4.99 or Annual £79.99 after that. No ads, no data sale.