Hello becky_s22, I seem to be having the same problem as the UnrealGear here, on my iPhone 5s. I had to disconnect my iPhone from iCloud photo library, since it took up all (!!!) the space on my iPhone, even with "save storage on iphone" option ticked, so I left about 3,5 gb of photos on my phone. About 1,5 gb is taken by apps and with no music on my phone this is generally all media I have there. However, I am repeatedly getting "Storage almost full" message.
Below is my storage screen from iPhone settings as compared to one in iTunes on my Mac (it is in Russian but you see the gist).
As obviously seen, iPhone shows that most of the storage is occupied by something unidentified, which is listed as "system" below, taking up 7,54 gb. This thing doesn't seem to be showing up on Mac but is still there. As far as I am concerned, I bought a 16 gb iPhone, not a 9 gb one. What can be done to solve this? Is restoring from backup necessary?
Thanks in advance, natarave