GPX, catalog route or just the distance?

What you choose for the route changes how your distance is measured.

With a route (your GPX or a catalog race)

• Your position is matched to the course, so your distance is the course distance, not the zig-zags of your GPS.
• Followers see the whole route, a finish prediction and how far you are from them.
• The race finishes by itself when you reach the finish line.
• You can turn on Start clock at the start line.

Without a GPX (race distance only)

• Your distance comes from your phone's GPS path, so it can differ from the official one a little.
• Progress, distance left and the finish prediction use the race distance you entered.
• There is no automatic finish: tap Finish yourself.

Free run

• No route, a goal distance is optional. Without a goal there is no progress bar and no finish prediction, and it never finishes by itself.

You can add a GPX later in Race settings, which switches the race to route-matching. Removing a GPX is possible only before the start.