Reddit mentions of Popsky GPS Tracker, No Monthly Fee Real Time GPS Tracker Locator for Vehicle, Waterproof Magnetic Tracking device Vehicle Monitoring System with Free App

It could be a GPS tracking device. Most such devices are well-labeled as such, but some are not.

• GPS trackers often are used with an external power source, such as one that you would attach to the internals of your car, in case it is stolen. The 7-pin port on the bottom of the device is used for power so that would support this theory (this is what lipo cables with different numbers of pins look like). Here is an example of a GPS tracker that still has the power cord attached. They almost always also have a battery power source (as yours does, as does the one in the link), so the power cord is optional.
  
  
• GPS trackers sometimes have a "SOS" or "help" button, which broadcasts your location and contacts an emergency service. That is what the "TOUCH" button on the top face of your device looks like. Here is an example of a GPS tracker with a SOS button.
  
  
• The dial on the side of your device could be used to adjust the strength of the signal it transmits. I have not found any examples of devices that do this, however.
  
  I would say the next step is get an electronics screwdriver and disassemble it. Most GPS trackers require a monthly service fee in order to function (though some do not, and tie into the network via a sim card. Your device may have a SIM card inside it. Even if it does not, taking apart the device may give you more information about who made it.