SD Maid SE (AKA SD Maid 2) is a file management tool for Android that specialises in maintenance. Its core purpose is freeing up space and removing unwanted data.

Features include:

Removing data that belongs to apps that are no longer installed (CorpseFinder)
Deleting expendable files, e.g. caches (AppCleaner)
User configurable filters for random files (SystemCleaner)
Scheduling actions (Scheduler)
Controlling/disabling apps (AppControl)
Storage overview (StorageAnalyzer)
Find duplicate data (