The best Stardust alternatives, compared

Why people look for a Stardust alternative

Stardust is a period tracker with a personality: daily cards tuned to your moon, sun and rising signs, a moon calendar, and modes for pregnancy and after birth (App Store). It has about 120,000 ratings at 4.8 on the US App Store. People leave for one of three reasons.

The 2022 encryption story

Stardust climbed to the top of the US App Store in June 2022, after the Supreme Court overturned Roe v. Wade. It had promised to encrypt users' data. TechCrunch then found that phone numbers of people who signed in that way were being sent to the analytics company Mixpanel, and after TechCrunch contacted it, the company quietly removed its end-to-end encryption wording from the privacy policy. In an update on June 30, TechCrunch reported that encryption keys made on the phone were being uploaded to Stardust's servers. The founder told TechCrunch that personal details were no longer sent to Mixpanel.

Today Stardust says "We do not sell data. Never have, never will" and that health data is tied only to a random account ID.

The privacy label

On the US App Store, Stardust lists purchases, identifiers and usage data under "Data Used to Track You", which is Apple's term for data used to follow you across other companies' apps and sites. Its Google Play data safety section says it shares no data with third parties. Both labels are filled in by the developer.

Less astrology, more tracking

If you liked the cycle part and skipped the cards, any app on this list gives you the tracker without the horoscope. Stardust's premium plan, Stardust Super, is $6.99 a month or $29.99 a year, and the company's FAQ says the free version "more than holds its own".

How we picked these Stardust alternatives

We read each app's US App Store listing, its Google Play page and the company's own privacy pages, and compared what someone leaving Stardust tends to ask:

• What it costs. The free tier, and what moves to a subscription.
• What the privacy label says. Especially the "Data Used to Track You" box.
• Whether you need an account. And where your entries are kept.
• What it tracks. Periods, trying to conceive, pregnancy, and the years when cycles change.
• Where it runs. iPhone, Android, or both.

If something here is out of date, write to us from the contact page and we'll fix it.

The five apps, one by one

Her Good Days: the best Stardust alternative overall

Best for: anyone who wants a full cycle and pregnancy app with no astrology.

Her Good Days covers every stage, from first periods to after menopause. In Private mode there's no account, and your logs stay on the phone in an encrypted database.

• A period calendar with your next period shown as a range, and estimated fertile days, labeled Not birth control
• Hot flashes, night sweats, brain fog and cramps, each with how strong it was, next to sleep, mood and food
• A pregnancy mode with your week, your baby this week, appointments, a kick counter and a contraction timer; keep it on the phone only, and delete it in one tap
• A doctor report for the dates you pick, as a PDF
• Download all your data in one file, or delete everything on the phone, from the app

It runs on iPhone and Android; teens 13 to 17 get a teen mode with no fertile days. More on period tracking and how your data is handled.

Clue: the like-for-like swap

Clue is made by BioWink. It predicts periods, logs a long list of symptoms, and has modes for tracking your period, trying to conceive, pregnancy and perimenopause, which you can switch between as life changes (App Store). It links with Apple Watch, Oura, WHOOP, Withings and Fitbit.

Best for: anyone who wants Stardust's range of modes without the horoscopes.

Pricing: free tier; Clue Plus is $9.99 a month or $39.99 a year, for deeper analysis and advanced predictions. Rated 13+, 4.8 from about 407,000 ratings.

Privacy: its privacy policy says health data "is never shared with or sold to advertisers". If you allow it, events such as installing the app or subscribing go to ad networks like Meta and TikTok. The App Store label lists identifiers as used to track you.

Flo: the most features, many of them paid

• Period, ovulation and pregnancy tracking, plus a Perimenopause Score and Menopause Timeline
• Anonymous Mode, so your health data isn't linked to personal identifiers
• An Apple Watch app
• Premium: daily insights, a Symptom Checker, a 24/7 Health Assistant and deeper pregnancy features

Best for: people who want lots of tools in one place and don't mind paying for some of them. The US listing shows purchases from $1.99 to $59.99 without saying which plan is which (App Store). Its privacy label lists purchases, location, identifiers and usage data as used to track you, more than Stardust's. Flo also has an FTC order on its record from 2021; our Flo alternatives guide covers it.

drip: everything stays on the phone

drip is a small open-source app from Heart of Code e.V., and its website says "Everything you enter stays on your device." Its App Store label reads "Data Not Collected". You can track bleeding, mood, pain, sex and temperature, use the symptothermal method to estimate fertility, export to a spreadsheet and lock the app with a password (App Store).

Best for: anyone whose first question is where the data goes. It's free on iPhone, Android and F-Droid. Expect a plain app with no articles, and only 59 ratings on the US App Store so far.

Apple Health: already on your iPhone

Cycle Tracking logs periods, symptoms, spotting and temperature, and predicts your period and a 6-day fertile window. It flags irregular, infrequent or long periods, and for users 40 and over the alert can mention perimenopause. You can export a PDF of the last 12 months for your doctor (Apple support).

Best for: iPhone users who want private tracking for free. With two-factor authentication on, cycle data in iCloud is end-to-end encrypted and Apple doesn't hold the key. There's no Android version, and Apple says it shouldn't be used as birth control.

Which Stardust alternative is best for you?

• You want one free app with no horoscopes, from periods to menopause: Her Good Days.
• You want Stardust's features from a bigger cycle app: Clue.
• You want the most tools and will pay for some: Flo.
• You want nothing to leave your phone: Her Good Days in Private mode, or drip.
• You have an iPhone and want nothing new to install: Apple Health.

For the bigger picture, our period tracker roundup puts seven apps in one table, and Her Good Days vs Stardust compares the two directly.