How to use BirdNET Pi in the field without home router access

My plan is to go into the field for a week and take a BirdNET-Pi with me without any Wifi access. I would like the BirdNET-Pi to listen to birds, record them and analyze the recordings. I would like to have access to the BirdNET-Pi via my smartphone, but I would not like to take a router or any other hardware with me.

The principles to do this were described in this thread HERE, but in order to be able to find it easier, I include a step-by-step workflow here:

• etch the usual 64-bit LiteOS on an SD card using Raspberry Pi Imager and using your home Wifi connection SSID and password
• connect to BirdNET-Pi on your home Wifi and use the one-line-installer to install BirdNET-Pi

From now on, every step can/should be executed in-the-field (without access to your home Wifi router)

• configure mobile hotspot on your smartphone/tablet to use exactly the same SSID and password as your home Wifi router (brilliant idea by davidmam) #119
• switch on hotspot of your smartphone
• BirdNET-Pi should now connect automagically to your smartphone and should be visible as a device in the mobile hotspot settings menu
• for iOS users, it might already work at this point by using birdnetpi.local in the Safari browser.

However, Android users probably have to perform the following additional steps:

• write down the local IP adress of your BirdNET-Pi that is displayed in the mobile hotspot settings menu
• ensure you have Juicy SSH or any other SSH client installed on your smartphone
• connect to BirdNET-Pi via your SSH client on your smartphone using the local IP and user name / password
• in the terminal, issue: sudo nano birdnet.conf
• change the line BIRDNETPI_URL= http://MY.LOCAL.IP.ADRESS
• save with CTRL+O, exit with CTRL+X
• in the terminal, issue sudo update_caddyfile.sh
• after a while, the BirdNET-Pi can be reached in your smartphones browser using the local IP adress