My phone has "airplane mode". Should I use it to turn off the ring?

You should NOT use airplane mode. It's designed to cut off all transmissions from the phone, including the data connection which is used by AccuTracking software to send the GPS data to the AccuTracking server. The tracking won't work under airplane mode.

Instead, you should adjust to ring volume to 0 or put it on vibrate if you wish to mute the phone.