Abstract: An intelligent wearable apparatus may include a user interface, a main body incorporating the user interface, and a mounting element connecting with two ends of the main body. In one embodiment, the apparatus can be a bracelet on the wrist configured to measure the acceleration and infers velocity and position from an accelerometer therein. In another embodiment, the apparatus is configured to display different colors in different situations, or conduct color coding for different functions thereof. For example, two apparatus in the present invention can be synchronized in static or dynamic manner so that any observer could easily and conveniently identify the social relationship between the people who wear the apparatus.