Portable input device, best practices for setup

We're working on a mobile 3D scanning device. The device is small handheld device, about the size of a gopro camera. The device has no display or other controls. The idea is that the user connects the device with either a computer / smartphone, sets up the desired params, and then walks around the object with the scanner pointed at the object.

Technically, we have both bluetooth and WiFi interfaces available on the device. What are some best practices / examples for the process of connecting the computer / smartphone with the device?

Our ideas so far are:

  • Add a button to the device to bring it into "bluetooth pairing mode", the user pairs the device using bluetooth menu on the computer, then downloads and runs our app to setup. All subsequent communication runs over bluetooth. (Like most bluetooth headsets)

  • When starting up, the device exposes a WiFi network, the user connects to that network and then opens a website in the browser. The website is served by the device and directly allows configuration. (Like some printers)

  • The user downloads our app, which then tries to establish a Wi-Fi direct (not too familiar with that technology) with the device. (I am not sure if something like that is used)

  • The user downloads our app, which prompts the user to plug in the device with a cable. Once plugged in, we either automatically set up bluetooth connectivity or we allow the user to set up their home wifi credentials for the device. (Apple magic keyboard does this)

I'd be glad for any advice on that.