Don't trust this company. You MUST use the app or the device is a brick.
You also MUST turn on "locations services" in order for the app to use bluetooth to talk to the device. There is ZERO technical reason for needing GPS location services for this to happen.
The ONLY reason that I can see for them requiring location services being on is that they want to spy on you....
I am a network admin, I do have some experience in this field.
Why don't the idiot YouTube reviewers tell you about this alarming fact? Perhaps they stay stoned too long to learn anything about what "location services" are