I have a number of Photon 2s that I am sending out to a customer. I have set up the Photon 2s with a particular network but I need to be able to change the Wifi network it connects to in a handful of instances. The (original) Photon went into a listen mode after pressing and holding the Setup/Mode button for a few seconds and then the Wifi network could be changed using the App. The Photon 2 "seems" to go into a listening mode (dark blue LED flashes) after pressing and holding the Mode button, but it doesn't create a wifi network to connect your phone to, like the Photon did. Any pointers?
You cannot change the Wi-Fi network credentials using the Particle mobile app on the Photon 2.
Developers will typically use setup.particle.io or the Particle CLI.
Product creators at scale will use on the of the Wi-Fi setup options, typically a custom mobile app.
To only add Wi-Fi credentials without affecting claiming or requiring a custom app, you can use a computer with the device connected by USB and Configure Wi-Fi or the Particle CLI.