In my Lumia 735 phone memory system is using 4.41GB space. How can I reduce the space?

[Windows Central Question]

In my Lumia 735 phone memory system is using 4.41GB space.

How can I reduce the space?
OS is windows phone 8.1 (update 2)

 

[Czesky]

Kidding me or something? It's the ammount used by the OS and you CAN'T reduce it. That's why most of Lumia devices have over 8GB of storage.

 

[v535]

I think MS should come up with DISM command for phones, to reduce footprint of OS. Win 10 would be good option.