I wonder if there's a way to use a dongle (or a small wireless Bluetooth device or something) to connect a physical SIM to a phone that doesn't have a physical SIM slot.
For internet access - sure. For messages - sort-of. For calls - troublesome.
As far as I know, smartphones don't have a protocol for accessing a remote cellular network connection in the same way as if it was internal, so the only viable way is to have a hotspot device that shares the connection over wi-fi.
