On the opposite to sonynixon, I don't recommend using cleaner and booster apps at all as they will clog your memory and cause numerous incompatibilities.
What I suggest is that you download Sony's Xperia Companion software on your PC/Mac and backup your important data, then perform a software repair. That will refresh you phone experience totally.
Check [https://talk.sonymobile.com/t5/FAQ/How-to-perform-a-software-repair-with-Xperia-Companion/m-p/1103057|this page] on Xperia forum for a guide.