Tethercell replaces one AA in your electronics and can remotely turn on and off your device. Tethercell with the Smartphone app can alert you when the battery power is low on your electronic. You can also set device schedules & timers. In the future you can find Tethercell enabled devices with proximity function.
Tethercell was originally funded on Indiegogo and now is available on the site for $27 for one Tethercell. Check out Tethercell HERE