There are two big problems with iTunes backups. And we can understand why you say "nay" to both of them. First of all, if you're backing up with iTunes or iCloud, you never know what files are covered. While you have to move an entire folder to your external drive, there's no way to check what's inside — not to mention selecting specific files for a backup.
Back up content
Create a copy of your iPhone or iPad content and schedule backups to keep your data safe with AnyTrans.
Try free
✕
Another thing is Terminal commands can go wrong —  and they often do. A single mistake can break the whole process, so you'll have to start all over again. The good news is you can actually back up iPhone to an external hard drive without iTunes and iCloud. The tool that you need for that is called AnyTrans for iOS.
✕ Remove app banner