Privacy Policy

1. Who we are and what this covers

This policy explains how the app “Period Calc” (حاسبتي, shown inside the app as “Period Calculator”) handles your data. The developer is Hossam Hamouda (“we”, “us”).

We have no copy of anything you record in the app. From the app, our one server receives only the anonymous usage steps and subscription notices described in section 4, and plain requests for the app’s settings file (also section 4). What this website’s server keeps is described in section 13.

2. The data you enter and where it is kept

The app saves what you enter in a local database (SQLite) inside the app’s private storage on your phone:

• Period start and end dates.
• Daily log: flow, moods, symptoms and the notes you write.
• Pregnancy information when pregnancy mode is on: the first day of your last period, from which the estimated due date is calculated.
• Fasting and make-up days (qada): days you missed, made up, or fasted even though your period was expected.
• Fasting planner: whether it includes Mondays & Thursdays and the White Days, and the make-up fasts you mark with “I fasted”.
• Events you plan (Hajj, Umrah, travel, wedding or other): name, type and dates.
• Your goal — “Track my cycle” or “Trying to conceive” — and the day you chose “Trying to conceive”.
• Prayer & purity: your school of fiqh (Hanafi, Maliki, Shafi’i, Hanbali or “Not sure”) and the day you tapped “My period has ended”.
• Settings: cycle and period length, language, Hijri display and adjustment, reminder choices (including the fasting, fertile-days, pregnancy-test-day and purity reminders), and whether the app lock and biometric unlock are on.

Every calculation — predictions, ovulation, Ramadan days, due date — runs on your phone. We do not collect this data or send it to any server, and the app needs no account or sign-in. The only exception is the anonymous usage steps in section 4: they show when you turn a reminder, the app lock, Face ID or fingerprint unlock on or off, or change the language — never your cycle or period length, or anything else in this list. Your goal, your school of fiqh, the day you tapped “My period has ended”, the fasting planner’s Mondays & Thursdays and White Days choices, the make-up fasts you mark, and the fertile-days, pregnancy-test-day and purity reminder switches are never sent, not even as usage steps.

3. Backups and moving to a new phone

The database is an ordinary app file, so it is included in your phone’s own backups when they are turned on:

• iPhone: in your iCloud Backup or computer backup, and when you transfer data to a new iPhone.
• Android: in Google’s automatic backup and in device-to-device transfer.

These backups live in your Apple or Google account, under your settings and their policies; we cannot access them. You control backups in your phone’s settings (on iPhone you can exclude the app from iCloud Backup).

Your PIN does not travel: on iPhone it is kept in the Keychain as “this device only”, so it never moves to another phone; on Android it is explicitly excluded from backups. After restoring onto a new phone, the app lock turns itself off and you can set a new PIN.

4. What we never do, and anonymous usage steps

• No accounts, no sign-in; we never ask for your email or phone number.
• No ads and no ad networks.
• No third-party analytics or crash-reporting tools, no tracking across apps or websites, and no use of the advertising identifier (IDFA / Advertising ID).
• We do not sell or share your data, or use it for advertising or research.
• No access to your location, contacts, photos, camera, microphone or Apple Health.

Anonymous usage steps (version 1.2 and later)

To learn which parts of the app help and where people get stuck, the app sends anonymous usage steps to our own server (apps.hossamhamouda.com). They reach it through Cloudflare, which protects the server and carries the connection, so Cloudflare handles your IP address as it does for every site it protects; our server itself stores no IP addresses, and no analytics company receives the steps.

• What is sent: when the app is opened and closed and how long it stayed open; which screens are opened; which buttons, features and settings are used (for example “opened the planner”, “used the daily log”, “turned a reminder on”, “allowed notifications”) — never what you logged or for which day; when the Premium page is shown (with where it was opened from, which set of free features this phone has, whether it has ever shown you a Premium preview, and its test group, if any), how long it stayed open and how a purchase or restore ends; on the Calendar screen, when a card is shown, tapped or closed — only which kind of card it is (forecast, fasting days or report); and, on days you use the app, whether you have Premium (plan, renewing or not). Each step carries its time, and with them go the app version, device type (such as iPhone, iPad or Android), system version, device language and App Store country.
• Never sent: your period dates, cycle or period length, flow, symptoms, moods, notes, pregnancy, fasting or make-up days, events, your goal, anything about fertility or trying to conceive, your school of fiqh, anything about purity, or anything you type. The trying-to-conceive and prayer & purity cards, the goal and school-of-fiqh choices, and the fertile-days, pregnancy-test-day and purity reminder switches send no usage steps at all; if you open the Premium page from one of their locked features, the usage steps only say it came from a locked feature, never which one.
• Not linked to you: the steps carry a random ID created on your phone — not your name, email, phone number or advertising ID. Turning sharing off, or deleting the app, deletes this ID from the app’s usage records on your phone; turning it back on creates a new one. The only exception is the subscription link described below, which keeps the ID it was created with. Your choice is kept with your backed-up app data, so restoring a backup keeps sharing off. Our server does not store IP addresses.
• Subscriptions: if sharing has been on at any time on this phone, Apple’s notices about subscriptions bought on this phone afterwards (start, renewal, cancellation, refund — with the product, price, currency and store country) reach our server through RevenueCat carrying that random ID — also after you turn sharing off.
• Kept 180 days, then deleted automatically. Used only to improve the app — never sold, shared or used for ads.
• Turn it off any time: Settings → Privacy → “Share anonymous usage”.

If you chose to share analytics with app developers in your phone’s settings, Apple or Google may give us anonymous, aggregated usage statistics and crash reports. They never include what you record in the app.

The only permissions the app may ask you for are notifications (for reminders) and Face ID or fingerprint (if you turn on biometric unlock). On Android the app also uses the “run at startup” permission, only to re-schedule reminders after the phone restarts. Internet access is used only for subscriptions (section 5), the anonymous usage steps (section 4) and the app’s settings file (below).

Settings file (version 1.2.1 and later): when the app starts and when you come back to it, it reads a small settings file from our server (apps.hossamhamouda.com). The file holds only switches that turn app features on or off or adjust them — no personal data. The app reads it even when usage sharing is off, and sends nothing about you; it is just an ordinary request. As with the usage steps, Cloudflare handles your device’s IP address on the way, and our server does not store IP addresses.

5. Subscriptions: Apple, Google and RevenueCat

Premium is an optional subscription. Payments are handled entirely by Apple (App Store) or Google (Google Play); we never see your card number or payment details.

To manage subscriptions we use RevenueCat, Inc., which processes this data on our behalf. When the app starts, and when you open the subscription screen, buy, or restore purchases, the app contacts RevenueCat — even if you never subscribe — to check your subscription status and show prices. RevenueCat receives:

• A random anonymous ID created on your phone, not linked to your name or email. From version 1.2, if “Share anonymous usage” has been on at any time on this phone, this is the same random ID that the usage steps carry (section 4), so a purchase can be matched to the anonymous steps before it; it stays the same even if you later turn sharing off.
• Purchase history: the store receipt or purchase token, product, dates, price and currency.
• Technical information: device type, operating system and version, app version, store country and language (to show the right price), and when the app was last opened. As with any internet connection, your device’s IP address reaches its servers.

RevenueCat receives no data about your cycle, health or notes; it gives us only aggregate subscription statistics (such as subscription and renewal counts). RevenueCat is bound by its data-processing terms to use this data only to provide its service to us and to protect it. It keeps subscription records while they are needed for your subscription to work and for legal, tax and accounting duties, or until we ask it to delete them at your request. Subscription data may be processed in the United States or other countries where RevenueCat operates. See the RevenueCat privacy policy, the Apple privacy policy and the Google privacy policy.

6. Reminders

Reminders are local notifications that the app schedules on your phone through the operating system. There is no notification server and their content is never sent anywhere. By default reminders show a generic text without details; you can show details in Settings → Privacy → “Show details in notifications”.

7. App lock, Face ID and fingerprint

Your PIN is never stored as is. The app keeps only a one-way hash of it (SHA-256 with a random salt) in the iPhone Keychain, or in secure storage protected by the Android Keystore, which other apps cannot read. The hash never leaves your phone, and we never receive it.

Face ID, Touch ID and fingerprint checks are done by the operating system. The app only receives “succeeded” or “failed”; it never sees or stores your face or fingerprint data.

While the lock is on, the app hides its content in the app switcher.

8. Export and sharing

The Premium “Export data (CSV)” feature creates a file on your phone with your period dates and daily log (flow, moods, symptoms, notes), then opens your system’s share sheet. You choose where the file goes (for example Files, email or a messaging app); from then on that copy is governed by that app or service. We never receive the file or see its contents.

The Premium “Report for your doctor (PDF)” is made entirely on your phone from your own logs: your cycles and their lengths, period lengths, heaviest flow and most logged symptoms (and, while pregnancy mode is on, the date it counts from). Your notes and Hijri dates are added only if you choose, and “Trying to conceive since” only if that is your goal and you keep that option on. You hand the PDF to your system’s share sheet yourself and choose where it goes; from then on that copy is governed by that app or service. The temporary file is deleted as soon as the share sheet closes, again at the next launch, and by “Delete all data”. We never receive the report or see its contents; if usage sharing is on, the usage steps only say that you shared a report — never its contents or options.

Links such as this policy or the subscription page open in your browser or the store.

9. Deleting your data

• In the app: Settings → “Delete all data”. This permanently deletes all periods, logs, notes, fasting days, events and pregnancy information, resets your settings (including your goal, your school of fiqh, the “My period has ended” mark and the fasting planner, fertile-days, pregnancy-test-day and purity switches), cancels reminders, removes the PIN and deletes any report file waiting to be shared.
• Or delete the app from your phone, which removes its database. On iPhone, iOS may keep the PIN’s hash in the Keychain after the app is deleted; it does nothing on its own and is replaced when you set a new PIN (“Delete all data” removes it). On Android, reinstalling the app can bring your data back from your Google backup.

Deleting data does not cancel a subscription; cancel it in your store settings. Older phone backups and files you exported stay until you delete them yourself. We cannot delete or recover your data for you, because we do not have a copy. To have your purchase record at RevenueCat deleted, email us the order ID from your Apple or Google receipt and we will ask RevenueCat to delete it.

10. Sensitive health data

Cycle, pregnancy and fertility data (including trying to conceive), and your religious practice (your school of fiqh and purity), are among the most sensitive data there is, so the app is designed to keep them on your phone. We never receive them, which means we have nothing to sell, share or hand over to anyone — advertisers, data brokers, employers, insurers or anyone else.

The operating system protects the app’s files by isolating them from other apps and by encrypting storage when your phone has a passcode. We recommend a passcode on your phone and the in-app lock.

11. Children

The app is a general menstrual-cycle tool and is not directed to children under 13. We do not knowingly collect personal data from anyone of any age, because the app sends us no name, email or contact details — only the anonymous usage steps in section 4. If the user is a minor, we recommend using the app with a parent’s or guardian’s knowledge.

12. Your rights

Your cycle data is on your phone, so you control it directly: view and edit it in the app, export it (Premium), and delete it at any time. The anonymous usage steps (section 4) carry only a random ID, not your name or contact details. Turning sharing off stops them and deletes the ID from the app’s usage records on your phone (the subscription link in section 4 keeps it); steps already sent are deleted automatically after 180 days. If you subscribed and want them deleted sooner, email us the order ID from your Apple or Google receipt. The laws where you live — for example Saudi Arabia’s Personal Data Protection Law or the EU GDPR — may give you additional rights. For any request about subscription data held by RevenueCat, email us.

13. This website

This website, periodcalc.app, uses no cookies, no analytics and no trackers, and loads nothing from other companies — no fonts, scripts or images from third parties.

The free calculators run entirely in your browser. The dates you enter are never sent to us or to anyone else.

A link made with “Copy link to this result” holds your dates in the part after “#”, which browsers never send to any server; anyone you share the link with can see those dates. If you ask an AI assistant built into your browser to use a calculator for you, that assistant sees what you ask it to enter, as on any other page; this website still receives nothing.

Like any web server, ours keeps an access log of requests, for security and to keep the site running: the IP address, the date and time, the page requested, the referring page (the page you came from, if your browser sends it) and the browser type. This log is rotated every day, and each day’s log is deleted automatically after 14 days. The web server inside the site’s container also keeps a small technical log without IP addresses (the date and time, the page, the referring page and the browser type); it is limited to 10 MB and overwrites its oldest entries. We never use these logs to identify or follow you, and we never share them.

Links to the App Store take you to Apple, where Apple’s privacy policy applies.

14. Changes to this policy

If we change this policy, we will post the new version on this page and update the effective date. If a change is significant — such as starting to collect a new type of data — we will explain it in the app’s update notes before it takes effect.

15. Contact

For any privacy question, email hossam.hamoda@gmail.com. Please don’t include health data in your message — we don’t need it to help you.