Euki, drip., Apple’s Cycle Tracking and Plum are all private period trackers for iPhone, in different ways. Euki and drip. keep everything on the phone. Apple’s is built in and encrypts your Health data. Plum, which we make, keeps your history on its servers so you get a backup and can share with friends, and it keeps advertisers out. The right one depends on whether you need a backup.
How we chose
We make Plum, and it’s on this list. There are no affiliate links. We read Euki’s FAQ, drip.’s site and App Store listing, and Apple’s page on iCloud encryption on October 22, 2026. An app made the list if it shows no ads, never shares what you log with advertisers, and lets you delete your data yourself.
Euki, for nothing ever leaving your phone
Euki stores what you track only on your device. Its FAQ says the company has none of your information, so there’s no account to make. You set a PIN, and you can have it delete your data on a schedule. The FAQ is honest about the cost. If you lose your phone or forget the PIN, the history is gone and nobody can get it back.
drip., for open source with an export
drip. is open source, and its site says everything you enter stays on your device. Its App Store listing says Data Not Collected, and you can password-protect, export and import your data. It predicts your next period and shows fertile days if you chart temperature and cervical mucus. Exporting now and then is your backup.
Apple Cycle Tracking, for privacy that’s already on your iPhone
Cycle Tracking lives in the Health app. Apple says Health is one of the categories it end-to-end encrypts in iCloud when your account has a passcode and two-factor authentication, so even Apple can’t read it. It covers the basics and works from an Apple Watch. There’s nothing to install.
Plum, for private from advertisers with a backup and friends
Plum is a full period tracker. It predicts your next period, fertile window and ovulation, sends reminders, and logs symptoms and moods in a tap or two. It shows no ads and doesn’t carry the code that shows them. It never asks to track you, and nothing is listed under Data Used to Track You. Sharing what you log for product analytics is a setting called Help Improve Plum, and it starts off.
Plum isn’t on-device. You sign in with Apple or Google, and your history lives in your account, so a new iPhone picks up where you left off. If you join a group of friends, they see your period days and predictions. They never see your symptoms, moods or flow, and you can stop sharing with a group whenever you like. You can delete your account and every log from Settings. Plum has no PIN of its own and no export, so it relies on your iPhone’s lock. Our page on what Plum does with your data names every outside service that gets anything.
What each App Store label says
Apple makes every developer fill in a privacy label. Data Used to Track You is the line that says whether an app shares data with other companies for advertising. Here it is for the trackers people ask about most.
| App | Data Used to Track You | Can share your cycle |
|---|---|---|
| Plum Period Tracker & Diary | Nothing. The section is empty | Groups of friends, several people at once |
| Euki | Nothing. The label is Data Not Collected | None |
| drip. | Nothing. The label is Data Not Collected | None |
| PrivateCycle | Nothing. The label is Data Not Collected | None |
| Clue | Identifiers | Clue Connect, one way |
| Stardust | Purchases, Identifiers, Usage Data | Friend Sync, several people at once |
| Flo | Purchases, Location, Identifiers, Usage Data | Flo for Partners, one partner |
Which one to pick
Pick Euki if you want no company to hold anything and can live with no backup. Pick drip. for the same thing plus an export you control. Use Apple’s Cycle Tracking if the basics are enough. Pick Plum if you want a backup and friends in a group, and you’re fine with your history on our servers but never with advertisers. To judge an app that isn’t here, use our ten-minute privacy checklist.
