Fitbit's Luxe tracker has a few smart features as well, although these mostly exist in some way on the Charge 4 and other Fitbit trackers. The Luxe can display call, text and other smartphone notifications on your wrist. You can mark texts as read, or reply with a set of quick responses or emojis.
It's also about three quarters as wide as a Fitbit Charge 4, and a hair thinner. So yes, the Luxe is a dainty little thing, which is nice for people like me who have small wrists.