Max Clean & Boost is a powerful yet simple tool to get the job done.
Free, no annoying ads, no privacy concerns.
CLEAN: Deep scanning to free up storage space (System Cache, Google Maps Cache, Thumbnail Cache, Downloaded Files, APK Files, Advertizing Cache, Call Log, Clipboard & Browser History)
BOOST: Performance boost (restart memory intensive apps, free up fragmented memory, close redundant background tasks).
Super small install size, you want to free up space, not add more junk!