Lulu vs Flo: an honest comparison of two period trackers
Flo is a large, account-based women's health app with deep content, a pregnancy mode and perimenopause tools. Lulu is a smaller iPhone tracker focused on mood: it learns how you usually feel in each phase, needs no account and keeps cycle data on your iPhone. Pick Flo for breadth and pregnancy; consider Lulu for mood patterns and a no-server privacy model.
Lulu vs Flo at a glance
Flo facts below come from Flo's US App Store listing, its help center and public regulatory records, checked in October 2026. Lulu facts are from our own product.
| Flo | Lulu | |
|---|---|---|
| Platforms | iPhone, Apple Watch, Android | iPhone (imports Apple Watch wrist temperature via Apple Health) |
| Period, fertile window, ovulation predictions | Yes | Yes |
| Symptom and mood logging | 70+ symptoms and moods | One-tap daily mood check-in, symptoms as bunny drawings |
| Mood forecast | Personalized insights (Premium) | Shows how you usually feel each cycle day, with a heads-up before harder days |
| Pregnancy | Pregnancy Mode with weekly updates | Not a pregnancy app |
| Perimenopause | Perimenopause Score and Menopause Timeline | Perimenopause mode |
| Partner sharing | Flo for Partners (pairing code) | Partner sync via a private iCloud link (Lulu Plus) |
| Health content | Large library, expert videos, Symptom Checker, Health Assistant | Short phase guides and this website |
| Account | Account-based, with an Anonymous Mode | No account |
| Where cycle data lives | Flo's servers | On your iPhone; no Lulu server holds it |
| Price model | Free tier plus Flo Premium subscription | 3-day free trial, then a yearly Lulu Plus subscription |
Where Flo is stronger
- Content depth. Flo has one of the biggest health libraries in the category, plus expert-led videos and a Symptom Checker in Premium. If you love reading about your body, it's hard to beat.
- Pregnancy. Flo's Pregnancy Mode carries you from trying to conceive through pregnancy week by week. Lulu doesn't do pregnancy tracking.
- Android and Apple Watch app. Flo runs on Android and has a watch app. Lulu is iPhone only.
- Community features. Flo's Secret Chats let you talk anonymously with other users.
Where Lulu is different
- Mood is the main event. A one-tap check-in each day; after a couple of cycles Lulu shows how you usually feel on each cycle day, with a gentle heads-up before harder days.
- No account, no Lulu server. Your cycle data stays on your iPhone. We never receive it, so we can't sell it, leak it or hand it over.
- Partner sync without the diary. Your partner sees your phase and next period with tips, plus today's mood, tomorrow's forecast and your fertile window if you choose to share them. Never your symptoms, notes or history.
- Doctor-ready PMS chart. Turn your check-ins into a chart (with CSV export) to bring to an appointment.
- A cute bunny. Symptoms are logged as little drawings of Lulu. It's lighter than a clinical checklist.
Privacy: the honest history
In 2021 the US Federal Trade Commission finalized an order against Flo Health over allegations that it shared users' health data with marketing and analytics firms, including Facebook and Google, despite promising privacy. Flo had to get users' consent before sharing health data and undergo an independent privacy review. In August 2025 a federal jury in California found Meta liable under state privacy law for collecting data from Flo users through the app; Flo settled with the plaintiffs before the verdict.
Flo has since added an Anonymous Mode and other privacy controls, and it's fair to say the company has invested heavily in privacy since. Lulu's approach is architectural: there is no Lulu account and no Lulu server that ever holds your cycle data. For more on how period apps handle data, see do period apps share your data?
Scroll to "App Privacy" on an app's App Store page. "Data Used to Track You" lists what may be used to track you across other companies' apps and websites. Flo's US listing names Purchases, Location, Identifiers and Usage Data there.
Who each app suits
| Choose Flo if… | Choose Lulu if… |
|---|---|
| You want a big health library and expert content | You mainly want to understand your mood and energy across your cycle |
| You're pregnant or planning to be soon | You want no account and cycle data that stays on your iPhone |
| You use Android | You use an iPhone and want partner sync that never shows symptoms |
| You want a free tier to start | You're happy with a 3-day free trial, then a yearly subscription |
Switching from Flo
You can start fresh in Lulu by entering your last period and usual cycle length; predictions improve as you log new cycles. Lulu also works with Apple Health. See our Flo alternative page for a broader list of options, including Clue and Apple's built-in Cycle Tracking.
Frequently asked questions
Is Flo safe to use now?
Flo settled with the FTC in 2021 and has added privacy controls like Anonymous Mode since. Whether it's right for you depends on how comfortable you are with an account-based app that stores data on its servers.
Is Lulu free?
Lulu has a 3-day free trial, then a yearly Lulu Plus subscription.
Does Lulu have a pregnancy mode like Flo?
No. Lulu focuses on cycles, mood and perimenopause. If you're pregnant, Flo or a dedicated pregnancy app is a better fit.
Can Lulu be used for birth control?
No. Lulu's fertile window is an estimate, and Lulu is not a method of contraception.
Sources
- FTC: FTC Finalizes Order with Flo Health (June 2021)
- TechCrunch: Jury rules Meta violated California privacy laws by collecting menstrual health data from Flo (Aug 2025)
- Flo Cycle & Period Tracker on the App Store (US)
- Flo Help Center: How do I set up Flo for Partners?
This page is for information only and isn’t medical advice. If something worries you, please talk to a doctor.
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