You might want to try an app like SD Maid. It has an option to find large files, and it can clean up all the cruft that collects over time.
Novatel Bagphone, Motorola Microtac, Qualcom Q-Phone, Motorola Startac, Sanyo MM-8100, Sanyo MM7400, Samsung A900 Blade, HTC Touch Pro 2, Sammy Epic 4G,
Currently Sammy Galaxy S III running Stock Rooted KitKat 4.4.2 because it's just that good. Knox don't scare me
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