Not OP, but I'm guessing by running the code on itself, i.e. turning the code into a QR code (or a series of them), then scanning those QR codes on the phone and reassembling them using a text-editing app on the phone.

In ye olden days we used cables to sync all of our apps and data to our phones.

But why not move the data over that cable? Some kind of iOS thing that made that more complicated than pushing an app to the phone?

With great difficulty...