1. A Free App Built for Learning
Epicycle is a free, ad-free educational astronomy application developed and published by FlowDevs LLC. It is designed for learners of all ages, families, students, and astronomy enthusiasts.
We believe learning tools should be private and respectful. Epicycle contains:
- No user accounts or logins: You do not need to provide an email address, password, or create a profile.
- No advertisements: We do not include third-party ad networks or behavioral tracking.
- No tracking or analytics SDKs: Epicycle does not integrate third-party analytics frameworks, telemetry beacons, crash loggers with user identifiers, or device fingerprinting.
- No remote app servers: The app computes planetary and star coordinates directly on your device using built-in astronomical algorithms and an offline catalog.
2. Device Permissions and On-Device Hardware
Epicycle requests only the hardware access necessary to provide its interactive sky features. Both camera and location permissions are strictly optional. The core learning lessons, constellation guides, space quiz, and offline sky map are 100% operational without granting any permissions.
Camera Access
iOS Permission: NSCameraUsageDescription ("Epicycle uses the camera to display an augmented reality overlay of constellations and stars over your physical sky.")
Android Permission: android.permission.CAMERA
When you activate the Live Sky feature, Epicycle uses your device's rear camera to show your physical surroundings beneath an augmented celestial overlay. Camera image frames are processed in temporary, volatile memory (RAM) in real time solely to render the sky view. Epicycle does NOT capture photographs, record video, write camera frames to disk storage, or transmit camera data off your device. Camera sessions immediately terminate as soon as you exit the Live Sky view or switch away from the app.
Location Access
iOS Permission: NSLocationWhenInUseUsageDescription ("Epicycle uses your approximate or precise location to calculate where stars, planets, and constellations appear from your viewpoint.")
Android Permissions: ACCESS_FINE_LOCATION and/or ACCESS_COARSE_LOCATION
To render accurate celestial altitude, azimuth, and local horizon lines in Live Sky, Epicycle requires your current coordinates. This calculation occurs strictly on your device. Epicycle does not track your location in the background, does not save a history of locations to disk, and never transmits your coordinates to FlowDevs or any external servers. In the offline Sky Map, you can also manually select preset global cities (such as London, Tokyo, New York, or Sydney) without enabling location services.
Motion & Orientation Sensors
Epicycle utilizes your device’s internal gyroscope, accelerometer, and magnetometer (compass) to detect which direction your device is pointed. This sensor telemetry is evaluated live to orient the celestial dome. Sensor data remains in volatile device memory, is never logged, and is never transmitted off your device.
3. Google Play Data Safety Declaration
For users downloading Epicycle from the Google Play Store on Android devices, FlowDevs LLC makes the following certified disclosures regarding Google Play's Data Safety standards:
| Category | Data Collected | Data Shared | Purpose / Handling |
|---|---|---|---|
| Personal Info | None | None | No accounts, names, emails, or IDs collected. |
| Location | None collected off-device | None | Ephemeral, on-device calculation for horizon. |
| Photos & Videos | None | None | Camera frames processed in RAM only; never saved. |
| Device or Other IDs | None | None | No advertising IDs or persistent hardware IDs. |
Security Practices: Because no personal data is collected or transmitted across networks by Epicycle, there is no personal data exposed to transit interception or cloud storage breaches.
4. Apple App Store Privacy Nutrition Labels
In compliance with Apple App Store guidelines for iOS and iPadOS, Epicycle qualifies under the "Data Not Collected" label:
- Data Used to Track You: None.
- Data Linked to You: None.
- Data Not Linked to You: None.
Apple may separately collect anonymized app performance telemetry and aggregate installation metrics if you have opted in via your iOS device diagnostics settings. That collection is governed directly by Apple's Privacy Policy.
5. Account and Data Deletion
Both Google Play and Apple App Store guidelines require clear instructions regarding user account and data deletion:
Epicycle operates completely account-free. Users cannot create an account, and the application does not store any personal user information on external servers. Because no personal data or account is maintained by FlowDevs, there is no account or personal data to delete.
If you wish to remove all local app data from your device, simply uninstall or delete the Epicycle application using your device’s standard application manager (on iOS, press and hold the app icon and choose Remove App; on Android, drag to Uninstall or go to Settings > Apps > Epicycle > Uninstall).
If you have emailed our support team and wish to request the deletion of your email correspondence, you may email us at clientsupport@flowdevs.io with the subject line "Data Deletion Request". We will promptly purge your message history from our support inbox.
6. Children's Privacy (COPPA & Google Play Families Policy)
Epicycle is an educational application built for curious people of all ages, including children under 13.
- Epicycle does not ask for or collect names, addresses, birthdays, email addresses, or personal identifiers from children or adults.
- Epicycle does not contain social networking features, chat rooms, forums, or user-generated content sharing.
- Epicycle complies with the United States Children's Online Privacy Protection Act (COPPA) and the Google Play Families Policy.
Parents and educators can confidently introduce Epicycle in homes and classrooms knowing that learning is 100% private, self-contained, and safe.
7. Data Retention and Third-Party Sharing
FlowDevs LLC does not receive, retain, sell, lease, or share personal data from Epicycle users with any third parties, advertising brokers, or data analytics providers.
8. Website Privacy and External Links
This website (epicycle.flowdevs.com) is hosted on modern cloud infrastructure. When you access this website, standard HTTP connection metadata (such as your IP address, browser user-agent, and requested page URL) is processed by our hosting provider to deliver web assets and protect against cyberattacks. We do not use marketing tracking cookies or advertising pixels on this website.
External Support & Email: Clicking support links opens your default email client to send messages to clientsupport@flowdevs.io. Emails you send are used exclusively to respond to your technical questions.
Charitable Memorial Link: Epicycle is lovingly dedicated to Gül Ateş. Our website includes an external link to No Stomach For Cancer (nostomachforcancer.org). That link directs you to an independent 501(c)(3) nonprofit. FlowDevs does not process donations or collect donor data.
9. Contact & Policy Updates
If you have questions or feedback regarding this Privacy Policy or Epicycle’s privacy practices, please contact FlowDevs LLC:
- Email: clientsupport@flowdevs.io
- Developer Website: flowdevs.io
- Support Page: epicycle.flowdevs.com/support
- Terms of Service: epicycle.flowdevs.com/terms
Any future modifications to this policy will be posted on this URL with an updated revision date.