Does Apple Watch have a triathlon app?

Hi

Apple Watch does not include a built-in app with specific support for tracking triathlons (ie via a single workout type). The Workout app can instead be used to track different activities separately.

You may find that a third-party app meets your needs.

To limit your searches to those iPhone apps that also include an app for Apple Watch, search the App Store via the Watch app on your iPhone (using the Search or App Store tabs), rather than via the App Store app.