Just began using this on Friday, but very happy with the results, so figured I would pass it along. My Stbx has been playing "hide the kid", when I show up. This has happened yet again this weekend, so I'm going to be in court on Tuesday morning and you can never have enough evidence right? I have not seen S4 in nearly two weeks as a result of this behavior, so each day on my way to the hotel, I stop by and drop off a little note and inexpensive toy by the front door. ( It's just my way of letting him know that I've not left him.) On Thursday, I dropped off a "Special" stuffed animal and very pleased with the results. You see, our instructions not only indicated times of possession but mandated he reside at the marital residence. STBX has a habit of dragging him all over town to sleep depending on what she has planned the next day......unfortunately the "Special" teddy bear now let's me know his location and sends text messages when he is not home by 10:00 p.m. It's been great over this short period and battery is saved by remaining off until movement triggers it. Here's a snapshot of last night past midnight.