Thanks for reaching out with a great question! We're currently a little understaffed in our mobile department, but I think that adding some iWatch support is on our list of things to add once we get the bandwidth! Hopefully we can get that functionality added soon.
Let me know if you have any other questions, or if there's anything else that I can do to help.
I think in this case you should contact iCloud Support and tell them about your suggestion. iWatch support is a great idea. This will help very much for hiking. This functionality will be great and will add a essence to your hiking.
Tim Newton wrote: Would love to see that I’m on the trail in Hiking Project by simply looking at my iWatch. Any chance you can add iWatch support to the app?
You can do that already, if you export a GPX file, you can import it into a free app named "Work Outdoors". Use your iPhone to import the track, and it will go into the watch app. Worked pretty well when I had my iPhone/AW3.