Some cars are already compatible with these gadgets. BMW's i Remote app has been available since January for Android smartwatches, and Hyun-dai has offered its app for Android smartwatches since early March.
Yet these devices are niche products, worn mainly by early adopters who enjoy testing technology before it goes mainstream. Consumer electronics analysts routinely compare today's smartwatches to digital music players before the launch of the iPod in 2001, or to smartphones before the debut of the iPhone in 2007.
Apple is betting it can make the Apple Watch feel indispensable, not gimmicky. But even if it succeeds, linking a smartwatch to a car may not feel essential. Android and Apple smartwatches are paired to smartphones, rather than using their own cellular connection, so it is not entirely clear what a smartwatch can do that an iPhone cannot.
"Although a watch is more available as it's always on your wrist, people always have their phones in their pockets or purses anyway," said Andy Gryc, a former automotive manager at QNX who is now a private consultant.
Grover, who has tested an Android smartwatch for the past year, said he sees benefits from pairing it with a car. Having a wrist-mounted computer spares consumers the trouble of pulling out their cellphones to use Hyundai's Blue Link service if they want to warm up the car or start the air conditioner.
"It's going to start as a little bit of a luxury -- something that the more tech-oriented people will be drawn to," Grover said. "Over time, that may start to change."