G7JJF APRS Client · Android App · Last updated: July 2026
G7JJF APRS Client is developed and maintained by Jon Welch, G7JJF, an individual amateur radio operator based in Eakring, United Kingdom. The app is distributed as freeware via the Google Play Store.
Contact: www.g7jjf.com
This app does not collect, store, or sell personal data on any server we control. Your callsign and GPS position are transmitted to the public APRS amateur radio network by design — that is the core purpose of the app. No advertising, no analytics, no accounts.
You enter your amateur radio callsign, SSID, passcode, home coordinates (QTH), and beacon comment in Settings. This information is stored locally on your device using Android SharedPreferences and is never sent to us or to any third party except as described below.
When you enable beaconing, the app transmits packets containing your callsign, GPS location, and beacon comment to the public APRS-IS internet gateway network (aprs2.net). This is the fundamental purpose of APRS and is expected behaviour for a licensed amateur radio operator.
⚠ The APRS network is a public system. Once transmitted, your position and callsign are visible to anyone using APRS software or websites such as aprs.fi. This is intentional and required by the amateur radio licence conditions under which the app must be operated.
The app also receives packets from the APRS network, including positions and messages from other stations. This data is processed locally and not forwarded to any service we control.
The app requests device GPS to:
Location data is used on-device only. We do not receive, store, or process your location on any server.
| Data | Where stored | Retention | Exported? |
|---|---|---|---|
| App settings (callsign, QTH, etc.) | SharedPreferences | Until you change or uninstall | No |
| Station log (heard callsigns) | Device storage (heard_log.json) | 7 days rolling | CSV / KML on request |
| Weather history | Device storage (weather_history.json) | 30 days rolling | No |
| GPS track log | Device storage (track_log.json) | Until you clear it | GPX on request |
| QSO log | Device storage (qso_log.json) | Permanent until you delete | ADIF on request |
| Packet cache (last 100 packets) | Device storage (packet_cache.json) | Session + one restart | No |
| Map tile cache | Android cache directory | Up to 50 MB; auto-pruned | No |
| ISS TLE orbital data | SharedPreferences | Refreshed every 20 hours | No |
| Message templates | SharedPreferences | Until you delete | No |
All data listed above is stored only on your device. You can delete it at any time through the app's Settings screen or by uninstalling the app.
The app makes HTTPS requests to the following public services. We have no affiliation with these services and do not control their privacy practices. Your IP address will be visible to each service when a request is made.
| Service | Purpose | Privacy policy |
|---|---|---|
| APRS-IS (aprs2.net) | Amateur radio packet network — transmits and receives APRS data including your callsign and position | aprs2.net |
| CartoDB / Carto | Map tiles (dark basemap) | carto.com/privacy |
| OpenStreetMap | Map tiles | osmfoundation.org |
| Esri / ArcGIS Online | Satellite imagery tiles | esri.com/privacy |
| OpenTopoMap | Topographic map tiles | opentopomap.org |
| Celestrak (celestrak.org) | ISS orbital TLE data for pass prediction | celestrak.org |
| RepeaterBook (repeaterbook.com) | GB repeater data for map overlay | repeaterbook.com |
| NOAA Space Weather (swpc.noaa.gov) | Solar propagation indices | noaa.gov/privacy-policy |
| aprs.fi | Web lookup fallback for stations not heard locally | aprs.fi/page/privacy |
Map tile requests include the tile coordinates (zoom/x/y) and your device's IP address. They do not include your callsign or GPS coordinates.
| Permission | Why it is needed |
|---|---|
| INTERNET | Connect to APRS-IS network, download map tiles, fetch propagation and repeater data |
| ACCESS_FINE_LOCATION | GPS fix for position beaconing and track log recording |
| ACCESS_COARSE_LOCATION | Fallback location for filter centering when GPS is unavailable |
| BLUETOOTH / BLUETOOTH_CONNECT / BLUETOOTH_SCAN | Connect to Bluetooth SPP TNCs and BLE TNCs (Mobilinkd) for RF operation. Bluetooth scanning is used only to discover TNC devices — it is never used to derive location (neverForLocation flag set) |
| FOREGROUND_SERVICE / FOREGROUND_SERVICE_DATA_SYNC | Keep APRS connection alive when the app is in the background |
| POST_NOTIFICATIONS | Message notifications, watchlist alerts, NWS bulletin alerts |
| WAKE_LOCK | Prevent CPU sleep during active TNC connections |
| REQUEST_IGNORE_BATTERY_OPTIMIZATIONS | Optional — prevents Android from killing the background service on devices with aggressive battery management |
This app is not directed at children under 13. It requires an amateur radio licence to use the transmission features. We do not knowingly collect any information from children.
Transmitting on the APRS network — including position beaconing, messaging, and iGating — requires a valid amateur radio licence. In the United Kingdom this means a Full or Intermediate licence issued by Ofcom. Receive-only and internet-display features do not require a licence. The developer accepts no liability for unlicensed use of transmission features.
All data stored on your device is subject to the standard Android application sandbox. Data files (log files, JSON stores) are in the app's private storage directory and are not accessible to other apps. APRS-IS connections use cleartext TCP as required by the protocol — this is inherent to the amateur radio APRS standard and the data transmitted (position, callsign) is already public by design.
Since no personal data is stored on servers we control, there is nothing for us to provide, correct, or delete on request. All your data is on your own device. You can:
If you are in the UK or EU and have questions about personal data, contact us at the address below.
We may update this policy if the app's data practices change. The current version is always available at www.g7jjf.com/aprs-privacy. Continued use of the app after a change constitutes acceptance.
Jon Welch · G7JJF
Eakring, Nottinghamshire, United Kingdom
www.g7jjf.com