In August 2025, a San Francisco jury found that Meta had illegally collected data from Flo's users in violation of wiretap law. It wasn't the first time Flo had been in trouble over data — in 2021, the FTC found that the company had shared sensitive health information with Facebook and Google despite promising users it wouldn't. The 2025 jury verdict just made official what many users had long suspected.

Since then, a lot of women have been quietly looking for somewhere else to go. If you're one of them, the challenge is that most alternatives have problems of their own — and very few are upfront about how they handle your data. This guide cuts through the noise.

Why switching is harder than it sounds

The obvious answer is "just download a different app." But there are two things that make switching genuinely complicated.

The first is your data. If you've been using Flo for a year or more, you have a meaningful history of cycle data that informs your predictions. Starting from scratch with a new app means months of inaccurate forecasting while it learns your patterns. Most apps don't offer any way to import data from Flo — so you're forced to choose between your privacy and your history.

The second is that most alternatives are doing a version of the same thing. They might not have made headlines, but cloud storage, account requirements (we wrote more about why no app should require an account), and opaque privacy policies are the norm in this category, not the exception. Switching from one app to another doesn't automatically mean your data is safer — it depends entirely on how the new app is built.

The right question to ask any cycle tracking app: "Where is my data stored, and who can access it?" If the answer involves a server, a cloud, or anything other than your own device — that data can theoretically be shared, subpoenaed, or breached.

What to look for in a replacement

Before we get to specific apps, here's a checklist of the things that matter when evaluating a cycle tracker from a privacy standpoint. These aren't nice-to-haves — they're the questions that separate apps that talk about privacy from apps that are built around it.

The privacy checklist
Does it store data locally on your device? This is the most important question. Local storage means there's no server to breach, no cloud to subpoena, and no third party who can access your information.
Is an account required? Requiring an account means the app knows who you are and can link your health data to your identity. No account requirement is a strong signal that the app isn't built around collecting your information.
Is the privacy policy written in plain English? Vague language like "we may share data with trusted partners" is a red flag. A genuinely privacy-first app should be able to say clearly and simply what it collects — ideally because the answer is "nothing."
How does the app make money? If it's free with no subscription option, ask how it's funded. Data monetisation is a common answer. A subscription model — even a very cheap one — aligns the app's incentives with yours.
Can you export and delete your data? Any app that makes it hard to leave or take your data with you is not building in your interest.

The current options

Clue

Clue is the most commonly recommended Flo alternative and it's a reasonable app. It's based in Berlin, which means it operates under GDPR — genuinely stricter data protection rules than US law. That's worth something.

The problems are practical rather than principled. Clue stores data in the cloud, which means it's subject to the same theoretical risks as any cloud-stored health data. The app requires an account. And the free tier has become progressively more limited — Clue has been aggressive about pushing users toward its paid subscription, and the UI redesign that rolled out in 2025 frustrated a lot of long-term users who found the new version clunkier than what they were used to.

For women who want a polished, well-researched app and aren't primarily motivated by data privacy, Clue is a reasonable choice. For women who are switching specifically because of the Flo data issues, it doesn't fully solve the underlying concern. If you're specifically considering Clue as your next app, we've written a detailed look at what to expect from Clue and what to watch out for.

Drip

Drip is a smaller, well-regarded tracker that's earned a loyal following among women who want something genuinely simple. It doesn't have the fertility-obsessed framing that dominates most apps in this category and its privacy approach is better than average. The main limitation is that it hasn't been updated as frequently as the larger apps and the prediction engine isn't as sophisticated.

Log28 (Android only)

Log28 is open-source, stores everything locally, and requires no account. If you're on Android and privacy is your primary concern, it's the closest thing currently available to what a lot of women have been asking for. The trade-off is that it's minimal to the point of being sparse — there's no iOS version, and the UI reflects its open-source origins.

The iOS gap: As of early 2026, there is no strong privacy-first cycle tracker available on iPhone. Log28 is Android-only. The open-source options that exist for iOS are either discontinued or haven't been maintained. This is the gap that needs filling.

The data import problem

One of the most common frustrations we've seen from women trying to leave Flo is the data import issue. Flo does allow you to export your data as a JSON file — but virtually no other app will let you import it. You're left with a file you can't use and the prospect of rebuilding months or years of cycle history from scratch.

This is a solvable problem. A cycle tracker that accepts Flo's JSON export format would remove one of the biggest practical barriers to switching. It's something we've built into Ferne from the start.

What comes next

There’s a version of this that works differently. Your data stays on your phone. You never create an account. The free tier covers everything you need — no paywalled basics, no upsell popups. And support for importing your existing data from other apps so you don't have to start from zero.

We're also paying attention to the things most trackers ignore. For example, the way hormonal shifts across your cycle affect ADHD symptoms is well documented but almost no tracker is designed to help you see or manage that pattern. Ferne is.

We’re not live yet, but early access is coming soon.

Ready to stop worrying about who’s reading your cycle data?

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The bottom line

If you're leaving Flo, the most important thing is to understand what you're trying to solve. If it's the data issue specifically, the only apps that genuinely address it are the ones built around local storage — not just ones with better-worded privacy policies.

Right now, the options for iPhone users in that category are limited. That's a real gap, and it's the reason Ferne exists. In the meantime, the checklist above gives you a framework for evaluating whatever you're considering — and for asking the right questions before you hand over your health data to another app.

For more on how cycle tracking apps handle your data — and what the technical difference between local and cloud storage means in practice — see our guide on what happens to your period data. And if you want to see how the most commonly recommended private trackers actually stack up, we've put together an honest comparison of the best private period trackers in 2026.