Jane asked –
“I’m nowhere near my iMac, and won’t be for weeks. I need to backup my iPhone onto my MacBook Pro or external hard drive today. How?!”
To which the answer is, suprisingly, use iTunes.
It turns out that once you have connected your iPhones to iTunes on another Mac you can just right click on the device and select backup like so:
Hopefully this will help other people in a similar situation in the future.