How to choose a private period tracker: 7 questions to ask any app

In short: a private period tracker is one whose business doesn't depend on your data. Check how it makes money, whether it contains trackers, where your data is stored, what happens to anything you type into its AI, and whether "delete" really means delete. You can check most of this yourself, for free, in a few minutes.

Your cycle data can reveal a lot: when you're fertile, whether you might be pregnant, your moods, your medications. In 2021, the US Federal Trade Commission said one of the biggest period apps had shared users' health data with Facebook and Google despite promising privacy (FTC). So "we care about your privacy" isn't enough. Here's what to ask instead.

1. How does the app make money?

If an app is free and shows ads, your attention, and often your data, is part of what it sells. Apps funded by subscriptions, donations or a one-time price have less reason to share your information.

How to check: look for ads in the app, and search its privacy policy for words like "advertising partners", "marketing" or "sell".

2. Does it contain trackers?

Many apps include third-party tools that send information about how you use them to other companies: analytics services, advertising networks, crash reporters. Even when they don't send your cycle dates, they can reveal that you use a period app, and when.

How to check:

• On Android: search the app on Exodus Privacy, a free service that lists the trackers inside Android apps.
• On iPhone: on the App Store page, scroll to App Privacy and look for "Data Used to Track You" (Apple).
• On Google Play: open Data safety to see what the app says it shares (Google).

3. Where is your data stored?

There are two main approaches, each with trade-offs:

• Only on your phone. Nothing reaches the company's servers. This is the most private option. The catch: no syncing between devices, and if you lose your phone without a backup, you lose your history. In a 2022 review, Consumer Reports recommended Drip, Euki and Periodical because they store data locally and don't allow third-party tracking (Consumer Reports).
• On the company's servers. This makes syncing, backups and sharing with a partner possible, but you're trusting the company with your data. If you go this way, look for a clear statement of where it's stored, who can access it, and that it's never sold.

Neither is wrong. Choose based on which features you need.

4. How is it encrypted?

You'll see the word "encrypted" a lot. It can mean different things:

• In transit: data is scrambled while it travels between your phone and the server. This is standard, and every app should do it.
• At rest: data is scrambled while stored on the server, so a stolen disk is useless. Also standard with major cloud providers.
• End-to-end: only your devices hold the keys, so even the company can't read your data. This is the strongest, and the rarest.

How to check: if an app says "encrypted", look for which kind. If it doesn't say end-to-end, assume it isn't.

5. What happens to what you tell its AI?

More period apps now include AI chat. Anything you type goes to an AI provider, so ask:

• Which company processes the messages?
• Are your messages used to train or improve AI models? With Google's Gemini, for example, the paid service doesn't use your prompts or responses to improve Google's products, while the free tier does (Google).
• Are your chats saved, and can you delete them?

6. Can you really delete everything?

Look for clear, in-app ways to export your data and delete your account, and read what "delete account" actually removes. Some apps delete your login but keep your data, or keep things like photos or chats until you ask separately.

How to check: the privacy policy should say what's deleted, how, and how long it takes.

7. What law protects you?

Your rights depend on where you live and where the company is based:

• In India, the Digital Personal Data Protection Act, 2023 gives you rights to access, correct and erase your personal data, and its detailed rules were notified in November 2025, with most duties phasing in over the following 18 months (PIB).
• In the EU and UK, GDPR gives you similar rights, including a right to erasure.

A good app explains your rights in its privacy policy and gives you a real contact, not just a form.

A quick checklist

• No ads, and no trackers on Exodus Privacy or the App Store label
• Clear answer on where data is stored, and that it's never sold
• Plain explanation of what "encrypted" means for this app
• AI chats not used for training, and deletable
• Export and full account deletion inside the app
• A privacy policy written for humans, with a real contact email

How Periodiva answers these

We'll be straight with you:

• No ads, no trackers, never sold. No analytics, advertising or crash-reporting tools.
• Stored on our servers, encrypted in transit and at rest, but not end-to-end, so it can sync across devices and you can share a slice with a supporter.
• Luna uses Google's paid Gemini service, so your chats aren't used to improve Google's products. Chats are saved to your account, and you can delete them.
• Export and deletion are in the app; for anything the app doesn't cover yet, email us and we'll delete it within 30 days.

The full detail is on how Periodiva handles your data. If you'd rather nothing ever left your phone, a local-only app may suit you better, and that's a completely reasonable choice.