Privacy Policy

Last updated: 23 September 2026

Android package: com.tjdax.stardex

Summary

StarDex is an offline constellation field guide. There is no StarDex account and no StarDex server.
The camera takes the sky photo you choose to save. The picture stays in your gallery on this phone.
GPS is used only on this phone to calculate which constellations are overhead. The reading is not uploaded to us.
Internet is used for Google AdMob ads, the advertising consent message, and Google Play purchases. The sky guide itself does not need a connection.

1. Who we are

This policy describes how the StarDex Android app (“StarDex”, “we”) handles information. Contact: tjdaxmail@gmail.com.

2. Information we do not collect

StarDex does not collect, store, or transmit to a developer server:

Your name, email, phone number, or an account (there is no sign-up)
Your photos. A saved constellation card is written to the device gallery through Android’s media store
Contacts, call logs, SMS, or files other than the photo you just saved
A copy of your GPS track, compass history, or field-guide progress

3. Camera

The camera shows the sky behind the constellation lines and takes a photo when you press the shutter. The photo is combined with the constellation lines on this phone and saved to Pictures/StarDex. Uninstalling the app does not delete pictures already stored in the gallery.

4. Location

Precise location (GPS) is used on the device to turn star coordinates into the sky above you. The app can also read the last GPS fix already stored by Android. StarDex does not send coordinates to a StarDex server. A fix can be slow the first time, and the phone does not need mobile data for GPS itself.

5. Sensors

The accelerometer and magnetic field sensor estimate where the phone is pointing. Those readings stay in memory while the sky screen is open.

6. Data stored on the device

The app stores, on this phone only:

Which constellations you have collected, and the gallery URI of each photo
Language choice, whether you accepted the camera and location explanation, and whether ads were removed

Uninstalling StarDex removes that app data. Gallery photos remain until you delete them.

7. Advertising

Unless you buy the one-time “remove ads” item, StarDex shows a Google AdMob banner at the bottom of the sky, field guide, story, and settings screens. A separate rewarded video is shown only if you choose “Polish the lens”. When ads are requested, Google AdMob may process:

Advertising ID
Device and app information
IP address and coarse location derived from IP
Ad interaction data

Google handles ad data under its own policies:

You can reset your advertising ID or opt out of personalized ads in Android settings. In the European Economic Area and the UK, a consent message may appear before ads are requested.

8. Purchases

Removing ads is a one-time in-app product sold by Google Play (remove_ads). Google Play processes the payment. StarDex only stores a yes/no flag on the device after Play confirms the purchase.

9. Children’s privacy

StarDex is intended for users aged 13 and over. The stories are written so a family can read them together. The app is not directed at children under 13 and is not part of Google Play’s Designed for Families program.

10. Data retention and deletion

On-device progress and settings remain until you clear the app’s storage or uninstall StarDex. Advertising data retained by Google is subject to Google’s retention practices. To ask about this policy, email tjdaxmail@gmail.com.

11. Changes

If this policy changes, the “Last updated” date above will be revised.

12. Contact

Email: tjdaxmail@gmail.com