Using GPS/GNSS
(Throughout this help file, the term "GPS" is used generically to refer to any GPS or GNSS device.)
If your phone or tablet has GPS capabilities, or if you have a external GPS device with Bluetooth capability, then the map can track your location. Use the GPS button 
on the right edge of the screen to control this. When you click this button the system will zoom to and highlight your location on the map.
GPS Accuracy
If you are going to use your GPS location to mark points on the map then we strongly recommend that you do NOT use the GPS built into your phone or tablet. The uncertainty produced by these devices is about 15ft (on a good day). We recommend that you interface your phone or tablet with an external GPS device that has an uncertainty of 1 meter or better (ie "submeter" device). Even if you can't afford an external GPS device, you can probably mark your points on the map by visually pointing and clicking with more precision than your phone's built in GPS.
GPS Status
For more details or to troubleshoot your GPS connection, select "GPS Status" from the main menu. This will display a screen showing additional details such as error messages and the uncertainty of your current location.
GPS Pole Height
In the GPS Status menu, there is an option to set the Pole Height. If your GPS is attached to a pole, type in the height of the pole. Diamond Maps will then correct the elevation of your plotted points to be ground level.
Datum Correction
By default, Diamond Maps assumes your GPS is broadcasting WGS84 Lat/Lon coordinates. This is the case with most GPS devices. However, some GPS devices broadcast NAD83 coordinates. This is usually the case if you are using a higher precision device that uses RTK correction. If this is the case, go to the GPS Status item on the menu and change the source datum to NAD83. The correction amounts to about a 3ft shift for most of North America.
Status Color
There is a GPS status indicator at the bottom of the map that displays the current accuracy reported by a connected GPS device. Green indicates that the GPS has a fix on you with an uncertainty of less than 200 meters. Red indicates no fix.
NTRIP Client (offline app only)
The Diamond Maps Offline app has an NTRIP client in it that allows Diamond Maps to relay correction information from an NTRIP server to a connected Bluetooth GPS device. This option is only applicable if you are connected to a Bluetooth GPS device that is RTK capable AND does not already have its own correction service built into the hardware or app that accompanies the hardware.
Uncertainty
A translucent yellow circle will be shown surrounding your location indicating the uncertainty of the GPS fix. The smaller the circle the more precisely your location is known.
Importing GPS Data
Most of this help article relates to doing a live interface with your GPS. If you have previously collected data points stored in your GPS device then there is probably a way to transfer those to your map. Most GPS devices have a way to export their data to one or more file formats that can be imported into a GIS application. This may require the use of some companion software that comes with the GPS hardware. Some common GPS file formats that can be imported into Diamond Maps include CSV, SHP, or GPX. See the Import article for more details.
"User Denied Location"
If you get the error message 'User Denied Location' that indicates a permissions issue. Click here for troubleshooting instructions.
Marking Points With GPS
See Marking a GPS point for instructions on how to get the most from your GPS device when marking points on the map.
Moving Existing Points To Align With GPS Location
If you have some existing features on your map that were marked by hand and you now want to use a GPS to correct their location, see Move To GPS option on Feature Form's Action Menu.
Connecting To An External Bluetooth GPS Device:
Using The Arrow 100 by Eos
Using The Geode by Juniper Systems
Using a Trimble GNSS device
Using The GNSS Surveyor by Bad Elf
See here for a list of other common GPS devices
Connecting Diamond Maps Offline To An External Bluetooth GPS Device
One advantage of the offline version of Diamond Maps is that it can communicate more directly with an external GPS device. For more information see Offline App.