You can pick and choose which of your iPhone apps back up to iCloudYou can manually select what app data gets backed up to iCloud if you're running low on space.
Anyone on the free, 5GB iCloud storage plan knows that that's not a lot of space at all. You'll fill it up fast, so you need to be judicious about what you store in an iCloud backup if you want the best iPhone experience. This is especially true if you have, say, both an iPhone and an iPad.
One way you can free up some additional storage to use elsewhere is by manually choosing what app data gets stored, and what won't!
Turning off app data doesn't mean that app won't return to your device during an iCloud restore, it just means the app's data will not return.
Typically the camera roll and document-centric apps are the most storage-hungry. If you decide to turn these off, just make sure you're okay with losing the data within them in the event of a restore. We'd suggest saving any documents or photos to your computer frequently to free up storage space.
Or you can of course upgrade you...
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You can pick and choose which of your iPhone apps back up to iCloud
