Application software and operating system will not work at same time. Operating system supports the application software. Operating system does the jobs which are essential to work the application like loading,compiling etc.
How Does The Application Software And Operating System Work Together?
When you use a program,, it sends commands to the computer. But the computer is just a heap of nuts and bolts and computer chips. It can't understand the commands by itself. So the operating system catches the commands and tells the computer what you want it to do.