are you running a Bubbleupnp server on a laptop/desktop? I think setting up Volumio on your iPad & not needing anything else assumes subscription to a paid service, called MyVolumio (they offer a 15 day free trial). (in which case it is the RPi which connects to your wifi when it reboots and you simply direct your browser to volumio.local on any device on your wifi network).
Lenco L75 in a very heavy plinth /Hadcock 228 /London Decca Blue /Croft SMA IV Octal with separate 2020 PSU/ Croft 7R monos /Harbeth SHL5
Fletcher .3 /Hadcock 228 / Denon 103R/ Croft HeadAmp /Croft Mega Micro II (2015) /Croft Series 5 MkIi /Markaudio SOTA Cesti B
Leak Troughline III GTA / Vecteur D-2.2 / Wadia 121 / Katana, Isolator & RPi /RFC & AntiCable