It was the same functionality, however the UI was better imo and the platform integrated with almost every service. And since I use Microsoft for work and Google for school for me it was nice to have one with everything I wanted in it. Maybe any 3rd party app would have worked that way but I haven’t found it.

It’s been awhile now, but I remember it took me about 10 seconds to add an event which was really nice and all the fields I cared about were right at the top, so I didn’t have to stop in the middle of a conversation to actually add an event.

That’s what I remember anyway, technically pretty much every calendar app has the same functionality, sunrise just had great UX/UI, and integration so I could avoid the big players.