Radar can spot obstacles in fog, while other technology "sees through" high-sided vehicles blocking your view.

雷达可对雾中的障碍物定位，而其他的科技手段可透过阻碍你视线的高大车辆看到前方。

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If you're in the middle of a city, with tall buildings blocking your view of the sky, that can be a problem.

CNN: Why your trusty GPS sometimes fails you

In addition, DASH7 fits beautifully below an iPad or other tablet without blocking your view, providing omnidirectional sound for watching movies and music videos for the ultimate audio upgrade for tablets, smartphones and laptops.

ENGADGET: Soundmatters' $250 Dash 7 portable Bluetooth speaker to debut at CES 2013