Tired of being on the go and having to search for an outlet you can use to recharge your phone? If researchers at Nokia and at the Queen Mary University of London are successful in their new joint endeavor, you might never have to think of hugging the wall while charging your phone ever again. As Science Alert informs us, the researchers have been working on a prototype smartphone that can be recharged using only the sound waves that we encounter every day when walking down the street.