If we leave for the rodeo without our cell phone, we'll run back into the house to get it.If we're 10 minutes down the road, we'll turn around.Chances are, we'll notice we don't have it before we leave the driveway because we're going to plug directions into the fairgrounds or arena and use the GPS to either help us find the way or get around any obstacles in our path by letting it route us around a traffic wreck.It alerts us to speed traps while other apps play music or help us keep in touch with our buddies who are ...