Proximity Shield acts as Arduino Shield via 1Sheeld

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1Sheeld proximity sensor shield

Use the proximity sensor in your smartphone and take a certain action if something or someone gets near your
phone. Learn more from the example page.

This shield is one of the sensor shields. Sensor shields allows you to tap into your smartphone’s sensors and use in prototyping with Arduino, you can get information from the surrounding environment and use
it to trigger a certain action. Learn more from the sensor shields tutorial.