Lefebure NTRIP Client

Lefebure NTRIP Client is the most popular standalone NTRIP client for Android. It connects to any Bluetooth GNSS receiver — including SparkFun RTK Facet, ArduSimple simpleRTK2B, Emlid Reach, and any u-blox ZED-F9P-based board — and streams RTK corrections from an NTRIP caster like RTKdata.com directly to your receiver. The app also supports Android mock locations, allowing other apps on your phone to use the centimeter-level corrected position.

Download: Google Play Store (free)

Requirements

• Android phone or tablet with Bluetooth and internet access (cellular data or Wi-Fi)

• Bluetooth-capable GNSS receiver (SparkFun RTK, ArduSimple, or any receiver outputting NMEA over Bluetooth)

• GNSS antenna with clear sky view

• RTKdata.com account with active RTK credentials (username starting with rtk)

Don't have an RTKdata.com account yet? Start 30-day Free Trial or View Pricing

Step-by-step setup

1

Install and open the app

1. Install Lefebure NTRIP Client from the Google Play Store.

2. Launch the app. You will see the main screen with connection status and data stream panels.

3. Grant all requested permissions (Bluetooth, Location).

2

Pair your Bluetooth GNSS receiver

1. Power on your GNSS receiver and ensure Bluetooth is enabled on it.

2. On your Android phone, go to Settings > Bluetooth and pair with your receiver (e.g., "RTK_GNSS", "RTK Facet-XXXX", or "SparkFun RTK").

3. Return to Lefebure. Tap the gear icon (Settings) in the top-right corner.

4. Under Receiver Connection, tap Bluetooth Device and select your paired receiver from the list.

5. Set Baud Rate to match your receiver (typically 115200 or 38400).

3

Configure the NTRIP profile

In Settings, scroll to the NTRIP section and enter the following:

North America

• Caster Host: rtk.rtkdata.com

• Caster IP (fallback): 13.56.117.10

• Caster Port: 2101

• Username / Password: From RTK Credentials in the internal dashboard (not website login)

• Mountpoint (ALL CAPS): AUTO (recommended) — or AUTO_WGS84, AUTO_ITRF2020, AUTO_ITRF2014

Europe

Australia

"Send NMEA to Server" must be ON. This is the number one issue users encounter. Without sending NMEA GGA to the caster, RTKdata.com cannot determine your position and cannot generate Virtual Reference Station corrections. You will see "0 GGA sessions" on your RTKdata dashboard and corrections will never arrive.

4

Enable GGA output

1. Still in Settings, find Send NMEA to Server (sometimes labeled "Send NMEA GGA to Caster").

2. Set this to ON / Enabled.

3. Set the GGA send interval to 5 seconds (default is fine).

4. Confirm by checking that the data stream panel shows outgoing GGA sentences after connecting.

5

Set up mock locations (optional)

To make other Android apps (e.g., Google Maps, field collection apps) use the RTK-corrected position:

1. On your phone, go to Settings > About Phone and tap Build Number 7 times to enable Developer Options.

2. Go to Settings > Developer Options > Select mock location app.

3. Choose Lefebure NTRIP Client from the list.

4. Return to Lefebure. In Settings, enable Mock Location Provider.

With mock locations enabled, every app on your phone will use the centimeter-level position from your external receiver instead of the phone's internal GPS.

6

Connect and verify RTK Fix

1. Return to the main screen and tap Connect (the play button).

2. The app will connect to your Bluetooth receiver and to the RTKdata NTRIP caster simultaneously.

3. Monitor the status display:

   • NMEA stream: You should see GGA, GSA, and GSV sentences flowing.

   • RTCM stream: Incoming correction data bytes should increment steadily.

   • Fix type progresses: GPS Fix > DGPS > Float > Fix.

4. Once Fix is shown, accuracy is at centimeter level. Typical convergence is 30-90 seconds.

Vertical reference (heights)

Heights from RTKdata.com are ellipsoidal, not orthometric (mean sea level). If your project requires orthometric heights, apply a geoid model in your GIS or surveying software.

Troubleshooting

Problem	Cause	Fix
0 GGA sessions on RTKdata dashboard	"Send NMEA to Server" is OFF	Enable Send NMEA to Server in Lefebure settings. This is required for VRS corrections.
"Server TCP Error"	Incorrect host, port, or no internet	Verify hostname spelling, port 2101, and that your phone has an active data connection. Try the IP fallback address.
Connection drops repeatedly	Weak cellular signal or app sleeping	Disable battery optimization for Lefebure in Android settings. Keep the app in the foreground.
Bluetooth pairs but no NMEA data	Wrong baud rate or receiver not outputting NMEA	Match the baud rate in Lefebure to the receiver's Bluetooth baud rate (typically 115200).
Stuck on Float, never reaches Fix	GGA not being sent or poor sky view	Confirm GGA is enabled. Move to open sky. Check satellite count (need 10+ satellites).
Mountpoint error	Lowercase or misspelled mountpoint	Type AUTO in ALL CAPS. Do not attempt to browse the source table.

Tips and tricks

• "Send NMEA to Server" is non-negotiable. Verify this setting every time you troubleshoot. It is the single most common cause of failed connections.

• Lefebure works with virtually any Bluetooth GNSS receiver — SparkFun RTK, ArduSimple, Emlid, Bad Elf, EOS Arrow, and generic u-blox boards.

• Use the data stream panel to confirm both outgoing GGA and incoming RTCM. If GGA lines are flowing but RTCM bytes stay at zero, the caster is not responding — check your credentials.

• Mock locations are powerful. Once configured, apps like DroneDeploy, ArcGIS Field Maps, and Collector can use RTK-corrected positions natively.

• For persistent connection issues, try switching from hostname to the direct IP address for your region. Some mobile networks have DNS resolution delays.