LG has adopted Samsung's multi window feature on the LG G4. This feature gives you true multitasking on your cellphone. The only real problem with this feature is that it is only good for a few apps. The apps that you can use this feature with are just stock LG apps that you probably don't use on a regular basis anyhow. Enabling all apps for use with multiwindow is pretty simple but requires you to be rooted. Once you are rooted use a root file manager and head to /system. There you will find the build.prop. Open it and search for this line "persist.splitwindow.support_all". Change the default setting to true. Then simply reboot your device.