I lost my phone once while at a mall. I used my laptop to track it. It pointed to the precise spot to the left of the mall food court entrance where the garbage can was located where I threw it away with a bunch of trash from the car. The bubble of uncertainty was centered on that position and was so small that the edge did not even reach the mall entrance itself just a few feet away. That was not fun. Smart phones are relatively heavy compared to most stuff the gets thrown in there and they sink to the bottom.