The most important thing: The Apple Watch is a watch first and foremost. You can choose from a bunch of different watch faces.

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Fitness is a big part of the Apple Watch. It can read your heart rate from those four sensors on the back of the device.

Apple

The fitness app will encourage you to meet certain goals in different categories like exercising and standing.

Apple

For example, the watch will remind you to stand and move around if you've been sitting too long.

Apple

You can also keep track of how many calories you've burned.

Apple

The watch shows you a ring that closes up as you get closer to your daily goals. Close all the rings and you've won the day.

Apple

The fitness tracker also syncs with an app on your iPhone so you can get a deeper look at your stats.

Apple

This is the home screen. It stores all your apps. You can pan around by swiping the screen to see more apps.

Apple

See that dial? That's the digital crown. You rotate it to navigate through the Apple Watch software. Pressing it brings you back to the home screen.

Apple

You can view incoming text messages on your wrist.

Apple

And you can reply to texts with canned responses.

Apple

Apple also created a new set of animated emoji that you can send instead of text.

Apple

Maps work on Apple Watch too.

Apple

You can get walking directions on your wrist. The watch will lightly vibrate when you have to make a turn.

Apple

If you press the button below the digital crown, you can view your contacts. Tap a contact to communicate.

Apple

One way you can chat with your friends is by drawing doodles that appear on their watch too. It's cute!

Apple

You can also share your heartbeat. Your friend's watch will vibrate in sync with your heartbeat.

Apple

You can also accept calls and talk to people through the watch.

Apple

Siri works too. Just ask a question into your watch like you would on your iPhone.

Apple

You can view photos stored in your iPhone.

Apple

Third-party apps can display notifications on your watch. It's up to you to choose which ones show up.

Apple

Developers can also write apps for the watch. For example, BMW is making an app that gives you stats on your car.

Apple

Third-party apps will be able to show glances of relevant information on your wrist. For example, you can get a notification when your flight is about to board.

Apple

A lot of functions on the watch will be controlled from a companion app on your iPhone.

9to5Mac

Find out more details on the companion app on 9to5Mac >>

You'll be able to make payments with Apple Pay. Just tap your watch against one of those NFC payment pads.

Apple

The Apple Watch will come in two sizes, in case you have a tiny wrist.

Apple

The watch charges with this magnetic charger. Apple says you'll have to charge it every night.

Apple

You can swap out the bands. Apple is making a bunch of different styles. Third parties will likely make bands after the Apple Watch launches.

Apple

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