Your router/device will obtain a dhcp lease directly from the phone. The iptables command will automatically assign a ttl of 65 to packets going out via usb0 so no router firewall customization is required.

adb command in tether script will auto start usb tethering on a rooted android running version 7.0 on pi bootup. change the connectivity service number if you are using a different android version. 33 is for 7.0.

on first try if you have not used adb shell yet, make sure usb debugging is enabled and the pi fingerprint is allowed (popup on phone screen).

this is for educational use only