You can use custom icons for Waypoints if you subscribe to GaiaPro.
1. Tap on the Waypoint Icon on the Main Map screen.
2. Select either "Create Waypoint" or "Create Waypoint Near Me".
3. Tap on the Waypoint Icon in the preview screen to choose a new waypoint icon, and then select the icon you would like to use to identify your waypoint.
Note: You can also change an existing waypoint icon by viewing a saved waypoint, tapping "Reposition" and following step #3 from above.