A Flo alternative
for PMDD and privacy

By Ben Jonas Goedeke · 6 min read · checked against its sources · updated 13 Oct 2026

Flo says on its App Store listing that it has over 570 million downloads, and for many people it does the job well. If you are looking for an alternative, it may be for one of two reasons: you want your entries to stay off a company’s servers, or you need a record of premenstrual mood that a doctor can use for PMDD. Those are the two things Tideline, which we make, was built around.

So this page compares the two on facts we could check today, each linked to its source: Flo’s US App Store listing and privacy label, Flo’s own privacy policy, and Tideline’s listing and privacy policy. Everything was checked on 13 Oct 2026. Apps change, so look again before you decide. Where Flo does more than Tideline, we say so.

Tideline and Flo side by side

TidelineFlo
AccountNone. There is no sign-up step at all.Its privacy policy says that when you sign up it collects your name, email, birth month and year, password, location, time zone and language. Anonymous Mode lets you use the app without your name, email or technical identifiers linked to your data.
Where entries are storedOn your iPhone only. We run no server for them.Its privacy policy lists Amazon Web Services as the processor for “storing all personal data when you use the App.”
“Data Used to Track You” on the App Store labelNone listed.Purchases, location, identifiers and usage data.
PMDD namedYes, in the app’s name.Not mentioned on the listing.
How strong each symptom wasRead from your sentence as none, mild, moderate or severe, which you can adjust, plus a 0 to 10 rating of how much the day got in the way.Over 70 trackable symptoms and moods. The listing doesn’t describe a daily severity rating.
Report for a doctorAfter two cycles, the week before each period set against days 4 to 10, as a PDF (part of Plus).Cycle report summaries you can download and share with your doctor. The listing doesn’t describe a week-before against week-after comparison.
PriceLogging, history, reminders and export are free. Plus is listed at $49.99 a year, $12.99 a month or $5.99 a week, with a free trial.Free to download with core tools. Premium is listed as several in-app purchases, from $1.99 to $59.99.
AdsNo ads and no tracking tools.Not stated on the listing. The privacy policy says some technical identifiers are used to measure which of Flo’s own ads work, and that this does not include health data.

Sources for the table: Flo’s US App Store listing (description, in-app purchases and privacy label), Flo’s privacy policy, Tideline’s US App Store listing and Tideline’s privacy policy. Privacy labels are filled in by each developer and are not verified by Apple.

Where Flo does more

This part matters if you are choosing, so here it is plainly. Flo covers far more ground than Tideline does:

If those are what you need, Flo may suit you better, and that’s fine.

Where Tideline is different

Nothing to sign up for, nothing on our servers

Tideline has no account. Your entries live in the app’s storage on your iPhone, and the doctor’s report and the export file are made on the phone too. If you speak your entry, the speech is turned into text on the device and the audio is never sent anywhere. When you subscribe, Apple handles the payment and a service called RevenueCat confirms it; neither receives anything you log. All of this is in our privacy policy.

The trade-off is real. Without an account, we keep no copy. Your entries come along in your iPhone backup, and you can export them as a file at any time, but a lost phone with no backup means a lost record.

Built for the PMDD record

PMDD is diagnosed from daily ratings over at least two cycles, according to IAPMD, and researchers compare the seven days before a period with days 4 to 10 after it starts. Tideline is set up for exactly that. You write or say one sentence a day, it picks out the symptoms and how strong they sounded, asks how much the day got in the way, and after two cycles lines the two weeks up in a report. It keeps a record; it does not diagnose. What a PMDD tracker needs in general is in apps to track PMDD.

Free to log, paid for the report

Flo and Tideline follow a similar model: tracking is free and a subscription adds more. In Tideline, writing your day, your history and calendar, reminders, Apple Health import and export of your own data stay free. The doctor’s report, tips chosen from what you logged and the full article library are part of Plus.

Moving over from Flo

You can bring your past period dates in through Apple Health, if they are there, or mark any past day as the day a period started. Then log one sentence a day from now on.

Before deleting anything from Flo, its privacy policy says you can request a copy of your personal data and ask Flo to delete it by emailing [email protected].

If you only want a private paper record

Our printable PMDD chart covers two cycles on three sheets, no app needed.

Keep the record your doctor needs. Tideline is a period and mood tracker for iPhone: write or say one sentence a day, and after two cycles it puts the week before your period next to days 4 to 10. No account, no ads, and your entries stay on your phone. Logging is free; the doctor’s report is part of Tideline Plus, a paid subscription with a free trial.
Get Tideline on the App Store

Common questions

What is a good Flo alternative for PMDD?

Look for an app that asks every day, records how strong each symptom was, and compares the week before your period with days 4 to 10 over at least two cycles. Tideline is built for that record and names PMDD; Flo’s US App Store listing did not mention PMDD when we checked on 13 Oct 2026.

Is there a period tracker without ads or an account?

Yes. Tideline has no account, no ads and no tracking tools, and keeps your entries on your iPhone. Its App Store privacy label lists no data used to track you.

Is there a free Flo alternative?

Tideline is free to download, and logging, history, reminders and export stay free. The doctor’s report is part of Tideline Plus, a paid subscription with a free trial. Flo is also free to download, with a paid Premium tier.

Can I move my data from Flo to Tideline?

Past period dates can come in through Apple Health if they are stored there, or you can mark past period start days by hand. Flo’s privacy policy says you can request a copy of your personal data from Flo.

Keep reading

Sources

© 2026 Ben Jonas Goedeke · Tideline keeps a record. It does not diagnose, treat or prevent any condition.