Advanced GPS

This tool requires a Pro license

The Advanced GPS options allows you to view detailed location information and manage a NMEA stream from a connected external GPS device. This location information will also be used for GPS based digitizing.

Note:Global Mapper Mobile® on iOS has been whitelisted by the following GPS vendors: Bad Elf, Dual, EOS, Juniper, Geneq. Please contact mobilehelp@bluemarblegeo.comwith any questions.

Connect to Device

Open the GPS companion app and confirm your GPS device is connected prior to opening Global Mapper Mobile®.

From the Main Menu in Global Mapper Mobile®, tap Advanced GPS > Connect to Device.

Location Info

View advanced location and accuracy information gathered from the external GPS. If RTK corrections are being used this information will be reported in the Location Info. To record this information as attributes for points created with a GPS Tap point create mode, enable the Configuration option to Add GPS Point Attributes.

Not all fields will be populated with every device. Global Mapper Mobile® displays the information is available.

Location - Reports the coordinate location from the internal or external GPS device being used.

Fix - This indicates the fix, if any, being applied from the GPS or RTK correction source. RTK Float and RTK Fix types indicate the correction is being applied from the connected NTRIP caster.

Confidence - Reports the quality of the horizontal and vertical positions being reported when provided from the external GNSS device.

Accuracy - The horizontal, vertical, and 3D accuracy as reported from the GPS device.

Course - The heading and speed of movement reported from the device.

Status - The connection status, satellite connectivity, RTK connection, and NMEA stream recording status are all listed.


View the satellites being used by the external GPS to determine location.

The satellite map will display satellites within range based on their location, with those to the north at the top of the screen. Those closer to the center of the map have a higher altitude on the horizon. Satellites not being used for location (that have a low signal to noise ratio) will appear as hollow circles.

Below the satellite map the number of satellites are displayed for each constellation. Tap on a name here to filter the display of satellites and information from each of these groups.

Expand a section for each constellation to see the signal to noise ratio for each satellite in range, represented as a bar and a number. Each list shows a count of how many satellites are in range for that constellation.

NMEA Stream

Shows the NMEA Stream as it comes from the external GPS. On this screen you can Record the NMEA stream to a text file, Pause the data stream, and Clear the data stream shown.

Tapping to Record in the bottom right of the NMEA Stream screen will begin recording the data. Once the recording has started the Record button will change to Stop Recording.

Tapping to navigate away from the NMEA Stream screen will prompt the user to stop recording, save or share the recording, or continue recording the NMEA stream in the background. Tap the Stop Recording option at the bottom of the screen to stop the recording and save or share it.

From the Save NMEA Log options, select to either Email, Upload to File Location, or Save to Map Folder.

  • Email - This option requires configuration of the default mail application on the device in order to generate the email. The NMEA Stream text file will be attached to the generated email.
  • Upload to a File Location - This option will save the NMEA Stream text file to a selected file location. The locations available will be the file sharing methods you have set up on the device.
  • Copy to Map Folder - This option will save the NMEA Stream text file to the folder location of the open Global Mapper Mobile Package file (*.GMMP) map file.