Meet the WiTenergy: a smart energy meter that pairs with your smartphone to provide you with energy consumption data in real-time. It measures voltage, current, wattage, frequency, and power. The device also has a programmable timer and lets you control and monitor energy usage of any appliance from your iOS/Android device.
The WiTenergy E100S is easy to use and simply helps you figure out ways to save energy. Just bring your smartphone, and you are ready to roll.