Starro Privacy Policy
Starro edits your astrophotography entirely on your device. It has no ads, no analytics, no accounts, and it never uploads your photos or any personal data anywhere. This page explains that in full.
Key Points
100% On-Device
Every edit, star detection and stacking operation runs locally. Your images never leave your phone.
No Account, No Tracking
No sign-up, no email, no analytics SDKs, no advertising SDKs, no advertising identifiers.
No Data Collected
We operate no servers for Starro and collect nothing. Uninstalling the app removes everything it stored.
Table of Contents
1. Data Controller & Scope
The data controller for the Starro mobile application (package com.observin.starro) is the individual developer who publishes the app on the Google Play Store under the Observin developer account. For any privacy enquiry, use the contact details in Section 11.
This policy applies to the Starro Android application. The Trailium app has its own policy at observin.dev/privacy.
2. What We Collect: Nothing
Starro does not collect, transmit, store remotely, sell or share any personal data. Specifically, the app contains:
- No advertising SDKs — there are no ads in Starro and no advertising identifier is read or used
- No analytics or crash-reporting SDKs — we receive no usage statistics or telemetry from your device
- No accounts — no name, email address or credentials are ever requested
- No location access — the app does not request or use your location
- No photo uploads — all image processing (editing, star detection, stacking, export) runs entirely on your device
Your images, edit histories and app settings exist only in Starro's private storage on your device and in the images you explicitly save to your gallery.
3. Permissions Starro Uses & Why
Photos / Media
Used to import the images you explicitly pick for editing and to save processed results back to your gallery. Starro never scans, indexes or transmits your photo library. You can also share images into Starro from other apps (Android share sheet); those files are processed on-device exactly like picked ones.
Notifications & Foreground Service
Long stacking jobs continue in the background; a local notification shows progress and completion. Notifications are generated on your device and involve no remote service.
No Other Permissions
Starro requests no camera, microphone, location, contacts or network-identity permissions. Any permission can be revoked at any time via Android Settings → Apps → Starro → Permissions; only the related feature stops working.
4. Sharing Between Observin Apps (Trailium Handoff)
Starro can hand processed frames to the Trailium app installed on the same device (and receive frames from it) to continue a star-trail or timelapse workflow. This transfer:
- happens entirely on your device through a protected app-to-app channel that only Observin apps signed with our developer key can access
- only occurs when you explicitly tap the handoff button
- never touches a network or any server
Frames received by the other app are then governed by that app's privacy policy (Trailium: observin.dev/privacy). Handed-off working copies are cleaned up automatically after transfer or after a short retention window.
5. Third-Party Services
Google Play Store
Starro is distributed via Google Play. Google collects install, update and crash statistics related to app distribution under Google's own privacy policy; that collection happens in the Play platform, not inside Starro.
That's the whole list
Starro embeds no other third-party data services. There are no ad networks, analytics providers, crash reporters or cloud processors in the app.
6. Legal Basis (GDPR)
For users in the EU/EEA/UK: the only processing of your content Starro performs is the on-device image processing you explicitly request. To the extent the GDPR applies to processing that never leaves your own device, the legal basis is performance of a contract (Art. 6(1)(b)) — providing the editing functionality you asked for.
Because no personal data is collected or transmitted, no consent-management platform is required and no international data transfers take place.
7. Data Retention & Deletion
We retain nothing, because we hold nothing. Everything Starro stores — imported working copies, edit histories, settings — lives in the app's private storage on your device.
- Delete app data: Android Settings → Apps → Starro → Storage → Clear data
- Uninstalling the app removes all of its private data
- Images you saved to your gallery are yours and remain until you delete them
8. Your Rights
You retain all rights over your data under applicable law (including GDPR access, rectification, erasure, restriction, portability and objection rights, and the right to lodge a complaint with your supervisory authority). In practice, because Starro holds no personal data about you, there is nothing on our side to access, export or erase — your device is the only copy, and Section 7 explains how to delete it.
If you believe Starro has processed personal data about you in any other way, contact us (Section 11) and we will respond within 30 days.
9. Children's Privacy
Starro is not directed at children under 13 (or the applicable age of digital consent in your country). Since the app collects no personal data from anyone, it also collects none from children. If you have a concern, contact us via Section 11.
10. Changes to This Policy
If Starro's data practices ever change — for example, if ads or analytics are added in a future version — this policy and the Google Play Data-safety declaration will be updated before that version ships, the "Last updated" date will change, and material changes will be highlighted in the app's update notes.
We encourage you to review this policy periodically.
11. Contact
Questions about this policy or your data rights? Reach out — we answer all privacy requests within 30 days.
Contact Us