DEVICE THAT RUNS ON BATTERY) CONSUMES BATTERY.. 1. RADIO/NETWORK ACCESS - ONE OF THE MAJOR "CONSUMER" OF BATTERY..NETWORKS MAY VARY FROM CDMA - 2G-3G-4G - LTE , WIFI , BLUETOOTH , NFC ETC.. ALL OF THESE NEED SPECIAL RADIO DEVICES WHICH GENERATE MICROWAVES AND HENCE NEED TO EAT UP LOT OF