Sometimes I have to take my headless system to places that I don't know the WiFi SSID/Password before hand. SSH does not reliably work via usb, which is a pain anyways with my enclosure.

Is there a wireless way to change SSID/Password settings on the fly. I'm a mechanical Engineer, I don't know complex linux concepts, maybe this is trivial.

Some consumer IoT devices broadcast there own network for initial config of home SSID/Password. Is that possible? Necessary equipment/software/code?

I have Debian 3.8 on Pi 2, and use /etc/network/interfaces for setting SSID/Password "manually"