Unknown Documents and Data on iPhone, how can I get rid of it?

[iMore Question]

Unknown Documents and Data on iPhone

Help! My iPhone has been running out of memory insanely fast, and I've been on a frenzy deleting my apps, messages, pictures etc and even doing a hard reset.
The problem is that the totaled memory in Settings which I counted manually is around 3GB, but iPhone says I've already used 10GB.
When connected to iTunes, it shows that my phone used 7.18GB of memory on documents and data. I cannot for the life of me understand where this 7.18GB of data is stored at, because I've clicked on every single app under Settings and none are using that much memory. I've also deleted and reinstalled some apps in hope of clearing memory but it's not working.
Someone help?!

 

[kataran]

Unknown Documents and Data on iPhone

It could be an array of things like botched updates or incomplete backups

Next time you connect to iTunes do a back up and then restore your device and you should reclaim most if not all your lost space

 

[Ledsteplin]

Re: Unknown Documents and Data on iPhone

You can't add up that in Settings. That's not everything. Have you deleted the photos in the "recently deleted" album? Have you deleted old messages. Some of it may be what they call "other". Sync with iTunes on computer to get rid of "other". Some may be cache on the phone as well as in apps. Delete cache wherever you can. Try using the app, Battery Doctor, to delete cache.