https://apps.apple.com/us/app/mega/id706857885
https://play.google.com/store/apps/details?id=mega.privacy.android.app&hl=en_US
If your iCloud is full and you want to back up more of your photos and videos download MEGA an encrypted cloud storage service that does exactly that. Back up and upgrade your cloud for free or get even more storage for $5 – $30 dollars a month.
You could also use mega to transfer big files between your devices. Mega is on iOS, Android, and online so you can share the files between any device.