I am sort of confused about how all this works. i have never turned my icloud back up switch "on" but someone told me today that all your contacts calendars reminders notes ect back up even if your icloud storage switch is "off". is this true? how does it work? so finally i decided to turn the icloud storage and backup switch on today for the first time and it told me now itunes wont automatically back up when i plug it in to itunes. can u still back it up to the computer to be safe even though i turned the icloud back up switch on? i have used about 20 gigs of space on my phone and it says i have 1.5 available and i have used 3.5 gigs of icloud storage space so how is that possible if when i go to settings and about my phone it says ive used 20.2 Gigs. im totally confused. what does icloud really back up when you choose to turn the switch on? i am just really confused about the syncing/ backing up process and even though switch is off it still backs stuff up? so why turn it on? sorry for all the questions but hopefully someone can help me. thanks
It is a bit confusing. Easiest way to understand this is to separate out iCloud versus local storage - I think you're confusing the two.
iCloud: you get 5GB of space in your iCloud account for mail and backups. If you turn on backups, when it's on WiFi, connected to a power source, and the screen is off, it'll backup photos and videos in the Camera Roll, Device settings (for example: Phone Favorites, Wallpaper, and Mail, Contacts, Calendar accounts), App data, Home screen and app organization, Messages (iMessage, SMS, and MMS), and ringtones. The 5GB of space on Apple's servers is why you show 3.5GB of free space with 1.5GB used. iCloud does not backup movies, TV Shows, music, and other media, unless you've purchased it under the same Apple ID you're using for iCloud. If this is the case, you can re-download movies, TV shows, music and podcasts as many times as you want. I tend to let the iCloud backups happen every night and restore is easier.
Local backups can be done if you turn off iCloud backups. You can then backup the "traditional" way through iTunes. Once iCloud backup is turned off on your iOS device, you should get the option back in iTunes, after you plug the iOS device back into your computer. You are only limited to the space on your iOS and computer's drives. I tend to do a local backup once a month or so. There's just something about local backups that puts me more at ease, still. I trust the cloud...but only to an extent. The good news is the apps, movies, TV shows and music, once purchased thorugh Apple, can be redownloaded.
I also use iTunes Match for the "rest" of my iTunes music, that was not purchased through iTunes. This essentially does do a backup of my entire 18,000 track collection. Still strongly recommend local backups for all media, especially since we paid for it.
See these articles from Apple for more information:
iOS: How to back up
iCloud: Backup and restore overview