Many GPS watches support using navigation files but most do not. In general the Garmin triathlon (XT) and trail running watches (Fenix) do and also Suunto's. To find out for sure refer to the spec table for your watch from DC Rainmakers product tool. Simply select your watch (or one you are looking at getting), hit the Product Compare! button. Scroll down looking for the "Navigate" section then look for the feature "FOLLOW GPS TRACK (COURSES/WAYPOINTS)". If it says "Yes" then you are in business. A nice thing about the watch based navigation, at least on Garmin, is that it will alert you to turns as I have programmed these files to have CoursePoints for the turns. For Garmin watches you will probably want to use the FIT file, for Suunto watches the GPX file.

Let's just start with Yes. There are a plethora of apps out there that will load the GPX file and display it on maps. The best maps in the area of these files are the OpenStreetMaps (OSM) files, I have found them to have the most accurate and up-to-date trails since users can update them directly. AllTrails and EveryTrail are apps available on Android and iOS that support loading GPX file and displaying your position on a map along with the track. Although Strava has some course following capabilities, currently their mapping and course technology is missing routing data to accurately make courses to follow, at least the Nasty series. The main drawbacks to the phone app strategy is that it won't notify you of turns and running the GPS powered on continuously seriously degrades battery life, depending on the adventure you have chosen. You'll likely make it through a Nasty on a full charge, but not a run around a volcano (except Mt. Tabor).

This procedure on Windows works for wifi and Ant+ based watches that support navigation files, and has been tested with 310xt and 920xt.

1. Save the FIT file on your computer where you can find it.

2. Hit the Start Button, in the search box enter %appdata%

3. Click through folders for Roaming, Garmin, and Devices

4. Open the folder for the device you want to use, the folder numbers are serial numbers, so higher numbers are later devices.

5. Open the folder NewFiles. 

6. Copy the FIT file into the NewFiles folder. Your watch should synchronize it.

1. Turn on your watch

2. Get to the main menu

3. Training > Courses >

4. Use the up/down arrows to select the desired course name and hit Enter

5. Use the up/down arrows to select Do Course and hit Enter

6. When you get start running, hit the Start button

7. While running a course there are several custom displays that are only available while navigating. One of them is a panel that shows you how far to the next course point and it's name. When you get there the watch will alert you and momentarily display the direction to turn and maybe some text.

8. When you are done running hit the Stop button.

1. Save the GPX file on your computer where you can find it.

2. There are several ways to get it to your phone. In each case when you open it on your phone note where you save it.

Open the app then look file a menu with GPX tracks. More on this later.