Those tiny sensors that attach to keychains or other items which allows you to wirelessly track things when they are lost have been around for quite some time. The 2 brands that get most of the attention are Tile and TrackR. On their face, they appear to be similar, but anyone looking for a slight edge should, look into TrackR over Tile. The TrackR's thinner sensors can do more and the user replaceable batteries aren't those special expensive batteries. An interesting feature of the TrackR devices is that you can also be used to figure out the location of your phone when you can't figure out where you left it. Both companies use Bluetooth with a range of roughly 150 feet of bidirectional signal. When you buy a large number of them, you can get the cost down to $10 to $15 a piece, making it affordable to track lots of items. Check out the most current options at:https://www.thetrackr.com
