The Cydia Tweak FAppSize has been officially released and works with devices that have iOS 9 or higher. FAppSize is a new cydia lets you adds a new menu to 3D Touch for displaying the storage size. By performing a 3D Touch gesture on an app, you can view the new menu labelled as “App Size”. If you have a non-6s device, then you can also make this hack work with tweaks like RevealMenu that artificially add 3D Touch like functionality to non-3D Touch devices. Once installed, from Settings you can configure FAppSize to display install size or include files created within the application
If you’re in to give this tweak a try, FAppSize is now available as a free package on Cydia’s BigBoss repository and fully supports iOS 9 and It works with iPhone 6s also iPhone 6s Plus. To install this program requires a jailbroken device (see if and how you can do the jailbreak to your iPhone by clicking here) and you need an Internet connection to download the package.