Privacy policy

Last updated: 6 October 2026

This policy covers the Stellumis app for Android and this website, stellumis.com. The short version: Stellumis has no accounts, no advertising and no analytics. To show weather and ISS passes for your area, the app sends an approximate location, rounded to about 5 km, to two services. Everything else stays on your phone.

1. Who is responsible

Bilal SELCUKOGLU
Mittlere Holdergasse 38
71672 Marbach a.N
Germany
Email: info@stellumis.com

This person is the controller under the EU General Data Protection Regulation (GDPR) and the contact for all privacy questions.

2. The Stellumis app

2.1 Permissions and what they are used for

• Camera. Shows the live sky behind the labels. The camera image is processed on your phone and is neither stored nor sent anywhere. An image is saved only when you take a photo yourself; it goes to your phone’s gallery (folder Pictures/Stellumis) and contains no location data.
• Location. Your position is needed to work out which stars and planets are above you. This calculation happens on your phone. For weather and ISS passes, only a rounded, approximate location leaves the phone (see 2.2). The app uses your location only while it is open, never in the background.
• Notifications. An optional evening reminder about sky events. It is created on your phone; nothing is sent. You can turn it off in the app’s settings.
• Internet and vibration. Needed to load the online data listed below, and for a short vibration when you have found an object.

You can withdraw any permission at any time in your phone’s settings. The sky view keeps working without internet; features that need a permission you have withdrawn stop working.

2.2 Data that leaves your phone

The app has no servers of its own. It requests data directly from the following services:

As with any internet connection, these services also receive your IP address and ordinary technical details of the request, such as the time and the app’s user agent. We have no access to their records. Their own privacy policies, published on their websites, apply to how they handle this information. Some of them, for example NASA and NOAA, are located in the United States; no location data is sent to them.

2.3 Data stored only on your phone

• Settings: language, night mode, temperature unit, notification choice, and whether you have completed the introduction and seen the privacy notice.
• Your observing journal: the date, the object, your notes and the place, rounded to about 1 km.
• Photos you take, in your gallery.

This data is not sent to us or anyone else, and it is excluded from Android’s cloud backup. Uninstalling the app deletes the settings and the journal. Photos stay in your gallery until you delete them.

2.4 Google Play

The app is distributed through Google Play. When you download or update it, Google processes data under its own privacy policy. Google gives us only aggregated statistics, such as the number of installs. If you have allowed your phone to share usage and diagnostics data with Google, Google may also show us technical crash reports (device model, Android version, the error itself). These reports do not contain your name, contact details or location.

2.5 What the app does not do

No user accounts, no advertising, no analytics or crash-reporting tools of its own, no tracking across apps or websites, no sale or rental of data, and no location access in the background.

2.6 Legal basis

Sending an approximate location to OpenWeather and Pollux Labs is necessary to provide the weather and ISS features you use (Art. 6(1)(b) GDPR). The transmission of IP addresses to the services in 2.2 is technically unavoidable for any online request; it is based on our legitimate interest in providing the app’s online features (Art. 6(1)(f) GDPR). The same legitimate interest covers the crash statistics in 2.4, which we use only to fix errors. Access to your location and camera is controlled by you through Android’s permission system.

3. This website

• Hosting and server logs. The site runs on a server rented from a hosting provider in Germany. When you visit, the server records your IP address, the date and time, the page requested, the referring page and your browser version. These log files are kept for 14 days to keep the site secure and are then deleted (Art. 6(1)(f) GDPR). The provider processes this data only on our behalf, under a data processing agreement (Art. 28 GDPR).
• No cookies, no tracking. Visitors are not tracked and no cookies are set. Cookies are only used for the site administrator’s login.
• Social media links. The icons for our social media profiles are plain links. Nothing is loaded from these platforms unless you click one; after that, the platform's own privacy policy applies.
• Fonts and images are stored on this server. The site does not load anything from Google or other third parties when a page opens.
• Email. If you write to us, we use your message and address only to reply, and delete them once the matter is settled unless the law requires us to keep them (Art. 6(1)(f) GDPR).

4. Children

Stellumis is not directed at children under 13. We do not knowingly collect personal data from children, and the app does not store personal data on servers of ours at all.

5. Your rights

Under the GDPR you have the right to access your data (Art. 15), to have it corrected (Art. 16) or deleted (Art. 17), to restrict its processing (Art. 18), to data portability (Art. 20) and to object to processing based on legitimate interest (Art. 21). Because the app stores nothing on servers of ours, we usually hold no data about you, but you can always ask us. You also have the right to lodge a complaint with a data protection supervisory authority, in particular in the country where you live or work.

6. Changes

If the app starts handling data differently, this page will be updated before the new version is released. The date at the top shows the last change.

7. Contact

Questions about privacy: info@stellumis.com