How do Flo, Clue and Nisaa compare for Muslim women?

Flo and Clue are the better general cycle apps, with bigger symptom libraries and more mature Android apps. Nisaa is the only one of the three that applies hayd, istihadah and nifas rulings, so it is the only one that can tell you whether to pray, whether to fast and how many days you owe. Which suits you depends on which of those two things you need more.

Here is the comparison, feature by feature. Where a point is about a company's own claim rather than something independently tested, it says so.

At a glance:

• Hayd, istihadah and nifas logic: Nisaa only, by the madhab you choose. Flo and Clue have none.
• Prayer and qada fast count: Nisaa only.
• Symptom library: Flo lists over 70 symptoms and moods, Clue logs a broad range of cycle, mood and symptom data, and Nisaa tracks fewer general symptoms.
• Community: Flo has Secret Chats, a Premium feature. We found none in Clue, and Nisaa has none.
• Android: Flo and Clue, yes. Nisaa is iPhone only for now.
• Mozilla privacy score: Flo 7 out of 10, Clue 8 out of 10, Nisaa not independently audited.

Where Flo wins. Flo is the most established of the three and has the largest library: its App Store listing describes more than 70 trackable symptoms and moods, a Symptom Checker (not available in the UK, EU and some other European countries) and Secret Chats, where members share tips with each other. Those last features sit behind Premium. If you want a community around your cycle, or the widest symptom list, Flo is ahead and Nisaa is not trying to match it. Its data history is real but has improved: for what the FTC found in 2021 and what changed since, see our answer on whether Flo is safe.

Where Clue wins. Clue scored 8 out of 10 in Mozilla's most recent privacy testing, ahead of Flo's 7. It is a Berlin based company working under the EU's GDPR, and its co-CEOs have said publicly that they will not hand a user's health data to any authority that could use it against her. It describes itself as science based and says it works with research institutions including Oxford, Berkeley and MIT; that is the company's own description, not something we have verified. Its free plan covers basic predictions, and Clue Plus adds deeper insights and partner sharing. Its apps are available on both iPhone and Android.

Where Nisaa wins, and where it does not. What neither Flo nor Clue does is the religious layer. Nisaa reads what you log and names your state as hayd, istihadah, nifas or tahara using the position of the madhab you choose, excuses your prayers while hayd lasts, and keeps a running count of the fasts you owe, so you do not tally them from memory. For why that count matters, see what a period tracker for prayer and fasting must do. It shows no third party ads and does not sell your personal information; our answer on the best period tracker for privacy explains what that rests on. The honest tradeoffs: it is newer, it has not been through the kind of large independent privacy review Flo and Clue have had, it tracks fewer general symptoms, it has no community, and it is on iPhone only for now, with Android on its way.

How to choose.

• If you mainly want a general cycle calendar, a large symptom library or an Android app today, choose Flo or Clue. Of the two, Clue tested better on privacy.
• If you need the app to tell you whether you are praying, fasting or owed a make up day, none of the general apps does that, and what to look for in a period tracker built for Muslim women sets out the full checklist.
• Nothing stops you using a general app for symptoms alongside Nisaa for the rulings, though that means logging in two places.

If you are leaving Flo specifically, the best Flo alternative for Muslim women walks through what to check before you switch. If you would like to try Nisaa, it is on the [App Store](https://apps.apple.com/app/id6756938661).

This page compares products and is not medical or religious advice. For anything about pain, irregular cycles or unusual bleeding, speak to a healthcare professional.