A startup Tuesday unveiled technology it claims can can simultaneously charge multiple different devices in a house, even through walls and around corners, by using the same radio spectrum as other wireless standards, such as Wi-Fi and Bluetooth. "You don't have to put that device in every room. You just put it into one room in your house and it will power all your devices," said Hatem Zeine, founder of Ossia, developer of the technology. "It's like your Wi-Fi signal. If you can get a Wi-Fi signal, you'll be able to get power."