How do I set my phone to not run anything unnecessary in the background when the screen is off? It seems to kill the battery fast. Smart actions? Is that the secret? Could anyone tell me how to set it up to work so only items I choose such as Pandora would continue to play with screen off? I also use wifi at home but the 3G/4G indicator is still in the tool bar, so, I guess it's still trying to use the network as well.