I feel like a smartwatch could make for a really fantastic wallet replacement.
Apple Pay, obviously, but then also boarding passes, driver's license/other ID, etc. I feel like how cheap they are (relative to a phone) means that if an officer is asking for your driver's license, people would have less reservation than if they were handing over a phone.
I don't think they are cheap at all. Although I do believe and hope that wallets will be replaced by something like the watch. I use ApplePay daily and any place or business that offers an electronic ticket option raises their chances of being frequented by me (movie theaters/ airlines etc.)