1. Introduction
SonicDrop ("we", "our", or "the app") is a mobile application developed by Moinfotech. This Privacy Policy describes our practices regarding the information that may be processed when you use SonicDrop on your Android device.
By installing or using SonicDrop, you agree to the practices described in this Privacy Policy. If you do not agree, please uninstall the app and do not use it.
2. Information We Do Not Collect
SonicDrop is designed to work without any data collection. Specifically, we do not collect:
- Your name, email address, phone number, or any account credentials
- The names, content, or metadata of files you transfer
- Your precise or approximate location
- Device identifiers (IMEI, advertising ID, etc.)
- Contacts or address book data
- Usage analytics, crash reports, or telemetry
- Microphone recordings (amplitude is read locally and discarded immediately)
3. How the App Works
SonicDrop detects a physical "bump" gesture using your device's accelerometer and microphone. This sensor data is processed entirely on-device in real time and is never stored to disk or transmitted anywhere.
Once a bump is detected, the app broadcasts a discovery signal over UDP on your local Wi-Fi network (port 49877) containing only your chosen device name and local IP address. This signal is limited to your local subnet and cannot reach the internet.
File transfer happens over a direct TCP connection between the two devices on the same local network (port 49876). Files are streamed peer-to-peer and are never routed through any server operated by Moinfotech or any third party.
4. Permissions Used
SonicDrop requests the following Android permissions and explains why:
- RECORD_AUDIO — Used only to read the ambient noise amplitude at the moment of bump detection. No audio is recorded, stored, or transmitted.
- BODY_SENSORS / HIGH_SAMPLING_RATE_SENSORS — Used to read accelerometer data for bump detection.
- ACCESS_WIFI_STATE, CHANGE_WIFI_STATE — Used to determine the device's local IP address for peer discovery.
- ACCESS_NETWORK_STATE — Used to check Wi-Fi connectivity before attempting a transfer.
- INTERNET — Required for TCP socket communication between devices on the local network. SonicDrop never makes connections to the internet.
- READ_EXTERNAL_STORAGE / READ_MEDIA_IMAGES, READ_MEDIA_VIDEO, READ_MEDIA_AUDIO — Used to let you select files from your device for sending.
- WRITE_EXTERNAL_STORAGE / MANAGE_EXTERNAL_STORAGE — Used to save received files to the SonicDrop folder in your Downloads directory.
- BLUETOOTH, BLUETOOTH_SCAN — Optionally used as a secondary fallback discovery mechanism. Bluetooth scanning is passive; SonicDrop does not pair with or connect to Bluetooth devices.
- VIBRATE — Used for haptic feedback on bump detection.
5. Third-Party Services
SonicDrop does not integrate any advertising networks, analytics SDKs, crash-reporting services, or social media SDKs. The app does not communicate with any third-party server at runtime.
The open-source Flutter framework and associated packages are used to build the app. These are compiled into the app binary and do not independently collect or transmit data.
6. Data Stored on Device
SonicDrop stores the following data locally on your device only:
- A display name you choose during onboarding (stored in SharedPreferences)
- A flag indicating whether you have completed onboarding (stored in SharedPreferences)
- Files received from other devices (saved to your Downloads/SonicDrop folder)
None of this data is transmitted to us or to any third party. You can delete the app and all associated data at any time via your device's app settings.
7. Children's Privacy
SonicDrop is not directed to children under the age of 13. We do not knowingly collect personal information from children. Since the app collects no personal information from any user, no special treatment for children's data is required.
8. Changes to This Policy
We may update this Privacy Policy from time to time. When we do, we will update the "Last updated" date at the top of this page. We encourage you to review this page periodically. Continued use of SonicDrop after changes constitutes acceptance of the revised policy.
9. Contact Us
If you have questions about this Privacy Policy or how SonicDrop handles your data, please contact us:
- Email: support@moinfotech.com
- Developer: Moinfotech