Cupertino (Reuters): More than two years after releasing the Apple Watch, Apple Inc has finally been able to replicate 1940s comic strip technology, an advance that analysts say will spur sales.

The Series 3 of the Apple Watch, released on Tuesday along with the much-anticipated iPhone X, features wireless LTE connectivity. That means customers will be able to make phone calls or send text messages from the watch without needing to have an iPhone nearby, as they do with earlier models.

The ability to make calls with a wristwatch has captured the imagination of tech enthusiasts at least since it was prominently featured in “Dick Tracy,” the comic about a private detective who, starting in 1946, used calls from his wrist to help bust bad guys.

“This has been our vision from the beginning,” Chief Operating Officer Jeff Williams said at the launch event.

“Now you can go for a run with just your watch and still be connected. It’s really nice to know you can be reached if needed.”

To be sure, Samsung Electronics Co Ltd has sold smart watches with mobile data connectivity since 2014, but the first devices were bulky and suffered from poor battery life because the data connection consumed extra power. They also require a separate phone number.

Apple claims its new Series 3, on the other hand, will have up to 18 hours of battery life and is just a fraction of a millimeter thicker that its previous Series 2. And it will have the same phone number as a customer’s iPhone, which will still be required for the initial set up of the watch.

Apple said that all four major US carriers will offer service for the watch, and AT&T Inc and T-Mobile US Inc both said it would cost an extra $10 a month.