![using greenify using greenify](https://i.ytimg.com/vi/giJZifgq3Mo/maxresdefault.jpg)
This is app allows you to block certain apps to start/run background processes. Something else you can do to improve performance and battery life is using something like Greenify. Those other apps mentioned here usually claim to speed up your phone or increase battery life by killing apps and processes to "free up RAM" or "empty cache", which usually results in the opposite because Android has its own way to manage RAM and services and it will restart killed apps and services and it will take longer for apps to open.
#Using greenify install
Nevertheless, when you run out of space on your storage or SD card and you can't install more apps, take more photos or copy more music you can try to use SD maid to delete leftover files from uninstalled apps to free up storage space. Sometimes it is intentional so that everything is back in place if you decide to re-install the app or so that you don't lose data (would be bad if uninstalling a camera app would delete all photos you took with it), sometimes it is not intentional because the dev didn't use storage the right way.
![using greenify using greenify](https://www.premiuminfo.org/wp-content/uploads/2017/08/use-greenify-without-root.jpg)
When you uninstall an app it is possible that data from that app remains on your internal memory or SD card (configuration files, database files, thumbnails and whatever else the app created). It is not an app that claims to "boost" your phone and increase performance or battery life, it is a disk cleanup utility for your internal memory and SD card.