With this app you won't have to switch between apps to make two things at once! Here are some screens:
Isn't that awesome? And this all can be on your device without flashing! It's because this is a module for Xposed Framework. Don't know what that is? Check THIS post.
While installed the Xposed Framework, dowload the module, activate it and reboot your device to take the effect. The mode should work on all newer versions or Android stock based, MIUI, AOKP or CyanogenMod.