The Android phone app QSO-One has Allstar on it.
Making contact with the app does not appear to use your physical node.
It would appear to be possible to have Allstar communication without having a physical node.
WT Mode doesn't require you to have a node number or a physical node of your own, though to connect, the node must be online and handshaking w/the system (and the node owner hasn't disabled WT access).
Many new users are requesting node numbers, not realizing this, and the numbers go unused.
I'd love to ask the QSO1 guy to explain this better in his documentation.
Thanks, all explained.