My phone has been giving me the "storage is full" message for quite some time now. However now it is preventing me from downloading or taking pictures on my phone when I have maybe at most 20 pictures on my phone and two apps. So I hooked it up to my computer and iTunes is saying I have 10GB of pictures/videos that are non-existent on my phone.
Have you checked your "Recently deleted" album? Maybe it takes up your storage. Since iOS 8, the pics and videos you deleted are not actually gone. If you want to make them disappeared you need to go to the "Recently deleted" album and delete them again. Otherwise you need to wait for 30 days they will be deleted automatically. You should check it.
There are just too many things that require physical storage. That's why Apple chose to lump a lot of things into the "Other" category. it's seems like your phone is filled with cached files and data. That can include:
- Documents & Data
- Safari browsing data
- Mail data
- iTunes data, including files that have been streamed (which can be BIG)...
Since iTunes categorizes cached files as Other, reported usage for Music or Videos might differ.
Deleting data, and then restoring is a good way, but you should back up first. or it will cause data lost.
In addition, you can try to clean up cache files frequently. This thread is for your reference.