watchcollect
Disciple
Since I run obviously the most used feature is sports tracking. But Siri is such a useful thing, I know you can use Siri on the phone as well but it is so convenient and intuitive on the watch, I use it to make lists, set alarms/reminders specially helpful at work as I keep forgetting tasks.
Also, after getting the watch (cellular) I just leave my phone at home when I go for runs - I use the watch for music and also in case of some urgent calls. In fact I have started leaving my phone at home a lot specially when going to the movies (bookmyshow app is available on the watch), buying groceries or any other small errands. It feels so good to just leave the phone at home and head out. During work from home days (sadly no more) it was great to just let the phone lie in one corner and I could take calls from the watch. I have noticed I waste so much time on my phone when it is near me during work, for example I get a call I take it on the phone then before you know it I am on instagram/whatsapp wasting time. On the watch just take the call and then continue with work. I know all of these are first world problems but the watch is such a blessing to have at least for my use case.
Now only if India would allow Apple Pay then I wouldn't even need my wallet. Just the watch and you are good to go.