The Lunecase is an innovative iPhone case that uses the phone's electromagnetic energy, rather than the iPhone's battery power, to light up when you receive a text message.
Every iPhone emits electromagnetic energy. While the conventional iPhone doesn't use this energy, the Lunecase has found a way to actually harness the electromagnetic energy and convert it into a useful function. The Lunecase works by deciphering an iPhone's electromagnetic energy source, either a call, text message or a notification, and using the energy to light up a corresponding symbol on the case. For example, if you've received an SMS message, a message bubble will light up on the back of your phone. The Lunecase helps you to save your phone battery because the phone no longer needs to light up the entire screen to show you a notification.
The Lunecase iPhone Case Lights Up When You Receive a Text
References: kickstarter & gigaom