Grand series allows you to use Multi window. With this feature you can make the phone run two applications at the same time. Here are some simple steps on how to enable and use it.
From Settings go to Device and tap on Multi window. On the Multi window screen enable this option. You could also enable this from the notification panel.
As soon as you enable this option it takes you to the home screen, where you could see a slide bar kind of thing with lots of applications. From the Multi window tray hold and then drop any of the application either on the top or bottom of the screen and then hold and drop any of the application on the other side.
With this you can make your phone run two applications at the same time. Here in my example I have tried the music player and Facebook to run at the same time.
With the Multi window tray open go to the bottom you could see the Create icon which allows you to save the multi window you have used, you could also edit this. Help is also available to explore more on this feature.