Apple Watch: What We Know About the Wearable

— -- The wait for the Apple Watch is almost over -- but there are still plenty of unanswered questions about the highly anticipated wearable device.

"One of the biggest surprises people are going to have when they start using it is the breadth of what it will do," Apple CEO Tim Cook said last week at a conference, according to the Wall Street Journal.

The watch comes equipped with Apple Pay and a rich ecosystem of apps that can help keep the wearer informed with nuggets of information throughout the day, such as a dinner date or a flight delay.

While there are still some unknowns, here is what we know so far from Apple about its flagship wearable.

When Does It Go on Sale?

Apple has not specified the exact date consumers will be able to finally strap the highly anticipated wearable on their wrists, but we know it's coming sometime in April.

What Are the Different Choices?

The Apple Watch is expected to begin at a price point of $349 and will come in three editions: Apple Watch Sport, the standard Apple Watch and a luxury gold edition. Consumers can expect to pay more for the high-end versions.

Apple is reportedly working on a redesign of its stores that will create an even more alluring environment for people browsing for an Apple Watch, according to a New Yorker profile of Jony Ive, Apple's senior vice president of design.

What Makes It Different From Other Smart Watches?

While other wearables focus on a touch screen, Apple is making navigation on the watch head easier by letting the users move the digital crown to toggle between apps.

The wrist is "a very interesting place" because users can glance at it while "you can't glance at a lot of other places on your body," Cook told ABC News' David Muir in an exclusive interview after the watch was announced last year.

"You can measure a lot of things from there and you can just get, honestly, a tidbit today of what all it can do," Cook said. "But I think it's huge."

How Big of a Hit Could It Be?

Apple could sell as many as 20 million of its watches this year, according to a forecast from CCS Insight, a technology analysis company.

"This highly anticipated smartwatch will create a frenzy of demand, catapulting it almost instantaneously to be the most successful smartwatch ever," a CCS Insight blog post predicted.