The watch can receive calls via the iPhone and has a built-in speaker and microphone for "quick chats." Apple recommends taking longer calls on the iPhone.
Some of the more unusual features include the use of haptic feedback for incoming messages, which Apple said feels like a "tap on the wrist," letting you know to look at the device. Users can reply to messages by choosing from a short, pre-written reply or dictating one through the microphone.
The watch also vibrates slightly when the maps app is being used, providing a different feel for left and right, so the user knowns which way to turn without looking at the watch.
Besides the three basic models, Apple is offering a half-dozen straps to suit different styles, including traditional leather, steel links and colored plastics. The watch also comes in two sizes, one 38 millimeters high and the other 42 mm high.
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