Apple Watch app for hiking
Unfortunately there are no apps that satisfy your needs.

The Apple Watch Series 2 can track your location using its GPS receiver, but it can't determine your altitude/elevation on its own. It's technically impossible. The GPS receiver in the Apple Watch Series 2 is not as capable as the one used in current iPhones.



You can, however, use an app like ViewRanger in conjunction with an iPhone 6, 6 Plus, 6s, 6s Plus, 7 or 7 Plus. These devices have built-in barometers that can be used to determine your altitude.

I hope this answers your question.