I have found that having the GPX file to load onto my smartwatch app, has been a very easy way to keep on track without needing to stop and reference my cell phone. I can do that from your webpage with a laptop, but just thinking that if I'm out for a day of hikes on multiple trails in an area, I can't easily do that unless I go back to my car and use the laptop and find a wireless network, whereas the mobile app I'd just need to be in cell range for it to work.
It sounds like you're hoping to be able to download a GPS track from our app to your watch, is that correct? If so, it's currently only possible to download our GPS tracks from our website. I know that this can be inconvenient, especially if you're hoping to make a decision about your route when you get the trailhead. If you use your mobile device to go to our website, I think that you might still be able to download the GPS track from there. However, I'm not sure where the file would save to, or if you'd be able to access it, but it might be a work around in the meanwhile!
Let me know if that helps, or if there's anything else that I can do for you!