Kool Tools: Comet app for iOS
WhatsApp for Photos from Comet is a free iOS app that instantly syncs your photos from your smartphone with your friends and family.
You can keep all your albums in Comet without deleting any of them. Go in the Comet settings -> Cloud albums -> select the album/albums that shouldn’t be stored on your iPhone. That’s it, the album stays on your phone but the photos inside are downloaded (you’ll need an Internet connection to access them).
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