My iMac is getting very old, and since i reallly only use my iPad Pro for nearly everything was thinking of just not upgrading and going iOS only. The only problem i have is how to back up a rather large iPhoto library, its a little over 1tb and growing. I know I can get an iCloud subscription, but is only one offline backup safe enough. I have heard of some people having iCloud errors. So other then google photos, which i use, is there another service I could use to back from iOS only and not use a Mac at all? Thanks.