My iPhone storage space is never released I have an iPhone 5c with 8GB of storage, out of which approximately 3GB is taken by the operating system.

I've always had issues with running out of space, notwithstanding the very few things I keep stored on it, but since some days I'm having the whole memory completely taken and I'm unable to take any picture.

I keep on deleting files (e.g. I delete media from WhatsApp/Messages and I move pictures from the iPhone to iCloud), but still the memory is never released and always stated as 100% taken, and I'm talking about a significant amount of files deleted/moved (approx. 200 photos and 10 videos).

I hence try to restart the device, close the applications (trying more generally to make the OS re-initializing the memory stats), but still no luck. The only (weird) thing that makes the memory release a bit is when changing the language.

My operating system is iOS 9.0.

I'm wondering what's going on, are the deleted/moved files cached somewhere? Is there any effective way to completely release their memory cells and get back my memory?
Open the Settings App on your iPhone, go to Photos &amp; Camera.

Under the mentioned menu, you will see 2 options: Optimize iPhone Storage and Download and Keep Originals.

If Download and Keep Originals is selected, this is the cause of your issue.
Choose Optimize iPhone Storage. (Be sure that your Photos are Synced/Backed up on iCloud or on your PC or Mac - This option should not delete any photos from iCloud, but just to be safe).

Hope my answer solves your issue. I checked the settings on my iPhone 6s 64gb.