If I understand correctly, smart phones have different modules that can be turned on and off (Cellular, Mobile Radio, GPS, WiFi, CPU, Bluetooth among others), but they don't necessarily draw any current just by being turned on. The GPS and bluetooth modules can both be activated, but as long as no app is asking them to do anything, they draw little to no current. I guess the same can be said about the WiFi module as it doesn't seem to draw much current if it's simply connected to a network, but not transmitting or receiving anything (as it usually is when the phone isn't in use). What I don't understand is how or why the mobile radio module draws so much current. It seems like it will draw a lot of current as long as it's activated and there's no WiFi connection regardless of whether any information is being transmitted or received, so why does it consume so much power? If it draws that much from simply sitting there actively listening to push-notifications then any app relying on push-notifications will cause a high current draw regardless of whether any data is being sent or received? Anyone out there that could help cure my curiosity?