I just bought the Nike+ Sensor for my iPhone 3Gs, and I had a few questions. 1a. Should I put it to sleep after every run so I can save battery? I heard people just leave it on, but just wondering. 1b. How do I know if the sensor is awake or if it is asleep? 2. I don't want to buy the Nike+ shoes, and I know there are ways of connecting it to your shoelaces. I was wondering, what if I just put it underneath the sole of my ASICs? Or is that a dumb idea. 3. Should I use the Nike + iPod APP or do you recommend that Runkeeper APP? I've searched but can't come to a conclusion. 4. When not using the Nike + iPod App, should I turn it off under settings to save battery, or is it safe to leave it on? Can't wait to test this thing out ! Haha.