Last updated: 8 October 2026
Privacy Policy
The short version. Kalender has no account and no server of its own. Your tasks and plans are stored only on your phone. Your calendar is read on the phone to plan around your meetings, and calendar data never leaves it.
Three things can leave the device: crash reports (on unless you turn them off), usage statistics (off until you agree; the app asks you once), both through Google Firebase and never with your task titles or calendar content, and subscription information: an anonymous identifier used to check whether Kalender Pro is active, plus the purchase record if you subscribe (through Apple or Google, and RevenueCat). There is no advertising and no advertising identifier.
1. Who we are
Kalender (“the app”) is developed and published by Heyisoft (“we”, “us”), based in Türkiye. Heyisoft is the data controller for the personal data described in this policy under the EU General Data Protection Regulation (GDPR) and the Turkish Personal Data Protection Law No. 6698 (KVKK). For any privacy matter, write to heyisoft@gmail.com.
2. What this policy covers
This policy covers the Kalender app for iPhone and Android, and these web pages. It tells you what the app handles, where it is kept, what leaves your device and why, and the choices you have.
3. What stays on your phone
The following is stored in the app’s own storage on your device (a local SQLite database and files). We never receive it.
| Data | What it is |
|---|---|
| Tasks | Title, duration, weight, energy level, whether it is important, and its status. |
| Day plans and history | Where each task sits in a day, tasks moved to another day, and the times you rebuilt a day. |
| Settings | Your day’s start and end, theme, motion and haptics, and which calendars to include. |
| Installation identifier | A random identifier created on the device, used to tell your records apart from those of another device if sync arrives later. It is never sent to us or to any service; it does appear in the records inside your export and backup files. |
| Local backups | A backup file each day; the last seven are kept. A safety copy is also written just before you restore a backup, import a file or delete all data, so that step can be undone. They live in the app’s private storage. |
Device backups. If you use iCloud Backup on iPhone or Google’s device backup on Android, your phone may include the app’s data in that backup. This is part of your phone’s settings and is handled by Apple or Google under their terms; we have no access to it.
Export and import. You can export all your data as a JSON file from Settings. The file is handed to your phone’s share sheet, and where it goes (Files, email, a cloud drive) is your choice. The file is not encrypted, so keep it somewhere you trust. Importing a file replaces the data in the app with the file’s content, after a safety copy is made.
Features that work only on your device. Routines (tasks that repeat) are kept in the same local database. Reminders, the morning summary, the evening preview and the ongoing notification are local notifications scheduled on your phone; there is no push server. Widgets, the Live Activity, Siri and Shortcuts (App Intents), the Android Quick Settings tile, app shortcuts and adding a task from the share sheet all run inside the app on your phone and send nothing to us. When you speak to Siri, Apple processes what you say under its own terms. “Break down”, which splits a task into smaller steps, uses Apple’s on-device model on supported iPhones; the task text never leaves the device.
4. Your calendar
With your permission, Kalender reads your calendar (EventKit on iPhone, the Android calendar provider on Android) so it can plan around your meetings. It reads events from the calendars you include: title, start and end times, and whether you declined an event, so declined events are left out. It also reads the names of your calendars and their accounts so you can choose which ones to include.
- Kalender never writes to or changes your calendar.
- Events are read when they are needed and are not copied into the app’s database, its backups or its export file. Only the list of calendars you chose to include is saved.
- Calendar data is never sent to us, to Firebase, to RevenueCat or to anyone else.
- You can withdraw calendar access at any time in your phone’s settings. The app keeps working with your own tasks.
5. What leaves your device
| Data | Recipient | Purpose |
|---|---|---|
| Crash reports | Google, through Firebase Crashlytics | Finding and fixing crashes. A report contains the technical trace of the crash and the app’s state at that moment, the device model, operating system and app version, and a random Crashlytics installation identifier. |
| Usage statistics | Google, through Firebase Analytics (Google Analytics for Firebase) | Only if you agree. The app asks once, on its second launch; until you agree, and if you decline, nothing is sent. Understanding which features are used, so we know what to improve. Events such as app opens, screens viewed and features used (for example, that a day was rebuilt), with a random app-instance identifier, the device model, operating system, app version, language, and an approximate country or region that Google derives from a masked IP address. |
| Subscription status and purchases | RevenueCat, and Apple or Google | Checking whether Kalender Pro is active, and processing, unlocking and restoring a purchase. To check the status, the app sends RevenueCat an anonymous identifier its software creates, with the app version, operating system and store country. If you subscribe, Apple or Google take the payment and RevenueCat also receives the purchase record (product, price, currency, dates and store transaction details). We never see your payment card. |
Crash reports and usage statistics never contain your task titles, calendar events or any other content you enter. They are not linked to your name or email address, which we do not have. They are not used for advertising and not used to track you across other apps or websites.
6. What we do not collect
- No account, sign-up, name, email address or phone number.
- No task content and no calendar content, ever.
- No advertising, no advertising identifier (IDFA or Android advertising ID), and nothing is sold.
- No precise location, contacts, photos, camera or microphone.
7. Turning off crash reports and usage statistics
In the app’s Settings › Privacy there are two separate switches. “Anonymous usage data” controls usage statistics; it is off until you agree and you can change your answer at any time. “Crash reports” controls crash reports; it is on by default and you can turn it off. Once a switch is off, the app stops sending that data. Deleting the app also stops all collection.
8. Legal bases (GDPR and KVKK)
- Usage statistics: your consent (GDPR Art. 6(1)(a); KVKK Art. 5(1)), given in the app and withdrawable at any time in Settings › Privacy.
- Crash reports: our legitimate interest in keeping the app working (GDPR Art. 6(1)(f); KVKK Art. 5(2)(f)). The data is minimal, not linked to your identity, and you can switch it off at any time.
- Subscription status check: our legitimate interest in offering Kalender Pro and knowing whether it is active (GDPR Art. 6(1)(f); KVKK Art. 5(2)(f)).
- Purchases: performance of the contract you enter when you subscribe (GDPR Art. 6(1)(b); KVKK Art. 5(2)(c)), and legal obligations such as keeping transaction records (GDPR Art. 6(1)(c); KVKK Art. 5(2)(ç)).
- Data that stays on your device, including your calendar, is processed by the app on your phone and is not received by us.
9. Service providers and transfers abroad
Google (Firebase) and RevenueCat process data on our behalf as service providers, and Apple and Google process payments under their own terms. Their servers may be located outside Türkiye and the European Economic Area, including in the United States. Where the law requires safeguards for such transfers (GDPR Chapter V, KVKK Art. 9), we rely on the standard contractual clauses these providers offer.
- Firebase: firebase.google.com/support/privacy
- RevenueCat: revenuecat.com/privacy
- Apple: apple.com/legal/privacy
- Google Play: policies.google.com/privacy
10. How long data is kept
- On your device: tasks, plans and settings until you delete them or delete the app. Daily backups are kept for seven days and then replaced. “Delete all data” in Settings empties the app’s database but keeps the safety copy and the last seven daily backups on the phone so the step can be undone; deleting the app removes all of them.
- Crash reports: kept by Firebase Crashlytics for up to 90 days.
- Usage statistics: event-level data is kept for the shortest retention period Google Analytics offers (2 months). Reports built from it contain only totals.
- Purchase records: kept by Apple or Google and by RevenueCat for as long as needed to provide the subscription and to meet legal record-keeping duties.
11. Your rights
Under the GDPR you have the right to access, correct, delete, restrict and port your personal data, to object to processing based on legitimate interest, and to complain to your local data protection authority. Under KVKK Article 11 you have the right to learn whether your data is processed and why, to ask which third parties in Türkiye or abroad receive it, to have it corrected or deleted and those third parties told, to object to a result against you that arises only from automated analysis, and to claim compensation for damage caused by unlawful processing. You can complain to the Personal Data Protection Board (Kişisel Verileri Koruma Kurulu) in Türkiye.
To use any of these rights, write to heyisoft@gmail.com. We reply within 30 days. Because we do not know your name or email and the data on our side is tied only to random identifiers, we may not be able to find a specific record; turning off the switch in Settings and deleting the app stops all further collection. Everything on your device is already under your control: you can export it, change it or delete it in the app.
12. Security
Data sent to Firebase, RevenueCat, Apple and Google travels over encrypted connections (HTTPS). On your phone, the app’s data sits in its private storage, protected by the operating system.
13. Children
Kalender is a general planning app and is not directed at children under 13. We do not knowingly collect personal data from children.
14. These web pages
These pages have no cookies, no analytics and no forms. They are hosted on GitHub Pages, and the heading typeface is loaded from Fontshare; as with any website, those services receive your IP address and browser details when your browser requests the page or the font.
15. Changes
We may update this policy as the app changes, for example when a new feature sends data somewhere new. Changes will appear here with a new “last updated” date, and material changes will also be announced in the app.
16. Contact
Heyisoft, heyisoft@gmail.com. See also Contact and support.