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You can backup photos from your iPhone 7, but you’d have to do as you’d asked, move them to the computer then to the external drive.
Sorry, there was a problem. Please try again later.Yes. You need a Mac or PC to facilitate the transfer.
I would recommend:
Sorry, there was a problem. Please try again later.I think the easiest thing to do is download photos to your computer hard drive and do a backup when you're ready and all new files added since your last backup will be downloaded.
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