There is no helping it, sand gets everywhere! In your shoes, your clothes, your food and especially in your electronics. All the little holes and spaces between buttons allows sand to filter through and damage our gadgets. Placing your smartphones, speakers and other gizmos in ziplock bags allows you to rest easy without fear of damaging your stuff! 

http://www.cbsnews.com/news/hitting-the-beach-how-to-safeguard-your-electronics/