The beauty of such surveys, which are also collected in Australia and many European countries, is that they cover the whole day (not just the time at work), and they also have a built-in accuracy check, since they must always add up to 24 hours a day.

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The Pioneer SmartCradle for iPhones is compatible with all GPS enabled apps, including MotionX-GPS Drive and is the first of its kind to incorporate a built-in gyro sensor and accelerometer combined with an external antenna for improved GPS reception and location accuracy, even if GPS signals are limited by high rise buildings and tunnels.

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