> For the complete documentation index, see [llms.txt](https://docs.premium-positioning.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.premium-positioning.com/guides/gnss-master-app.md).

# GNSS Master (app)

These steps connect a GNSS Master (app) to the Premium Positioning correction network over NTRIP, using GNSS Master app (Android/iOS). They assume you already have your NTRIP credentials.

### Before you start

* Your NTRIP username and password, from your Premium Positioning welcome email or your account on the customer portal.
* GNSS Master app (Android/iOS).
* A working internet connection on the controller or phone.
* A clear view of the sky at the point you are measuring.

### Network settings

These are the same for every Premium Positioning customer. Only your username and password are unique to you.

* Server or host: rtkpremium.xyz
* Port: 2101
* Mountpoint: COMMON
* Protocol: NTRIP

### Steps

1. What you'll need: GNSS Master is a brand-agnostic app (published by Bad Elf) that connects to many Bluetooth/BLE GNSS receivers - u-blox-based units, ArduSimple, and others - and feeds them NTRIP corrections. You'll need: your receiver powered on and paired to your phone, the GNSS Master app installed, and your personal Premium Positioning NTRIP username and password from your welcome email. Use YOUR OWN credentials.
2. Pair the receiver in your phone first: Before opening the app, pair your receiver in your phone's system Bluetooth settings. GNSS Master selects from already-paired devices, so it must show up there first. Some BLE receivers connect inside the app instead - if yours isn't listed, that's expected; you'll pick it in the next step.
3. Open the GNSS Receiver Connection page: Launch GNSS Master and open the GNSS Receiver Connection page (from the navigation drawer / menu, or via the gear/settings icon next to the receiver connection). Wording varies slightly by version - look for the receiver connection or device settings screen.
4. Choose the connection mode and connect: On the connection page, open the Mode dropdown and pick how your receiver links: 'Bluetooth' for classic Bluetooth (SPP), or 'Bluetooth LE' for BLE. (GNSS Master also supports USB Serial/OTG and TCP/IP.) Select your receiver from the list, then press Connect. You should see live position data once linked.
5. Open the Corrections page: Open the Corrections page (sometimes 'Correction Input', from the navigation drawer or a gear/settings icon - label varies by version). This is where you tell the app where to get RTK corrections.
6. Set the correction Mode to NTRIP Client: On the Corrections page, open the Mode dropdown and select 'NTRIP Client' - so GNSS Master pulls corrections from an NTRIP caster.
7. Add a new NTRIP connection: Press the '+' button (Add NTRIP Connection) to open the NTRIP Client dialog. If asked for an NTRIP version, choose V2 if available; if it doesn't connect, fall back to V1. Field labels vary slightly between versions.
8. Enter the caster address and port: In the NTRIP Client dialog, enter the caster host/address rtkpremium.xyz and Port 2101 - the same for every customer. Protocol is NTRIP.
9. Enter the mountpoint: For the Mount point ('Mountpoint' or 'Data stream'), enter COMMON (in capitals). If the app offers a 'Get'/source-table button next to the field, you can tap it to list streams and pick COMMON - typing it directly works too.
10. Enter YOUR NTRIP username and password: In the Username and Password fields, enter the personal credentials from your welcome email - unique to you; do not share them. If you can't find them, contact support; the connection won't authenticate without valid credentials.
11. Enable Send NMEA GGA: Tick 'Send NMEA GGA to Base Station' ('Send GGA' or 'Send position'). The COMMON stream needs your approximate position to send the right corrections, so this must be ON. The app sends your position automatically once the receiver has a basic fix.
12. Save and connect: Press Save. The new NTRIP connection appears in the list - select it and press Connect. Watch for corrections flowing (an active/connected state, incoming bytes, or a falling correction age).
13. Confirm RTK Fixed: Open the GNSS Status page and check the fix type: Single → DGPS/Float → 'RTK Fixed' (\~1 - 2 cm). If it stays on 'RTK Float', give it a clear sky view and a minute or two. Once it shows RTK Fixed you're receiving Premium Positioning corrections and ready to work.

### If the fix will not hold

GNSS Master is brand-agnostic and works with many Bluetooth/BLE GNSS receivers, not just Bad Elf hardware. Menu/field names (Corrections vs Correction Input, Mount point vs Mountpoint, gear icon vs navigation drawer) vary by app version and platform - match the described screens. If it won't authenticate, double-check credentials and try NTRIP V1 vs V2; if it won't reach RTK Fixed, ensure 'Send NMEA GGA' is enabled and the antenna has open sky.

For more, see RTK corrections troubleshooting and Fix inconsistent RTK accuracy on site.

### Need help

Support is available 24/7. Include your receiver model, the mountpoint, the solution status, and the correction age when you get in touch.