A free program for Android, by Klein Tools Inc..

Inspecting underground structures and making sure that no one is below you is an important part of any drilling operation. For many years, this was done using a tool known as a “borescope”, which is a long, slender, and generally S-shaped tool that is inserted into the ground and allows you to view the area below.

The problem with this tool is that it is very difficult to use, as it requires you to stick your arm into the ground to hold it in place. This is not only painful, but can also result in the loss of your arm.