My wife has an iPhone 6s and I am trying to understand the way in which the device uses local storage. Her photos are very important to her and as such, I want them to be backed up safely. So we pay for extra storage on her iCloud account and her photos go there. Are they also stored on the device? Also, can they be deleted to make more available space on the local device but remain on the iCloud?
I am not very familiar with iOS devices.
Best Answer
iCloud Photo Library is not a backup solution, it's a sync solution.
It can be used as a backup but I don't recommend it. There's other solutions, like Dropbox or BackBlaze, that can serve as an offsite backup (using the 3-2-1 backup strategy).
When you use iCloud for photos, all the photos will be synced to each device signed-in with that iCloud account. Deleting a photo/video on any of those devices will also delete it from all the other devices when they re-sync. See this Apple Support site for more info.