Q: Where can i see my battery status on display screen?

Status? Upper right corner? But if you mean in percentage, no you can only enable that feature on an iPhone and maybe on the iPad, i'm not sure.

But i use a free App available in the app store. (Battery Level)

Go to: Settings -> General -> Usage -> Battery Percentage -> ON.

Like i said, that feature isn't available on the iPod touch.

jesterwylde, that option is not available for the iPod, What you said was in the Users Gudie for iOS 6 for the iPod but was corrected in the Users Guide for iOS 6.1 on the iPod.