Remember how as a kid you played with this particular toy, which is essentially a science experiment to demonstrate how sound travels? You hold a tin can or paper cup on one end, which is attached to a similar can or paper cup on the other via a string, and talk to one another like using a telephone. Skype for String does just that, where it delivers a method of near distance “calls” without eating into your precious minutes of your mobile plan, and you need not worry about the lack of battery life or spotty signal coverage, either. In addition, it is fully waterproof, and there is no need to shout whatsoever. The only danger? Someone tripping all over the string.