Pause button is available for download here: https://play.google.com/store/apps/details?id=com.vgmoose.pausebutton

Pause Button will pause any currently running app, no matter what it is. It can then be safely resumed. It's more fun when playing games that lack such an option, but, once again, it can be used on any application on the phone.

Root users only.

Disclaimer: You may find yourself in situations where the Android OS is waiting on a process to return, but it can't because it's paused. In these events you will have to reboot. Be responsible.