I'm beginning work on an app and one of the requirements is that there be some visual indicator for the user that displays their devices' connectivity status. I'm wondering if there is any research on the subject because it strikes me as a bit redundant since iOS and Android already have status indicators. The app doesn't take full control of the screen so the OS chrome will still be visible. 

The app does require network connectivity for certain features and there is a offline functionality strategy established. If a user attempts to make a remote call while offline, a dialog will appear. My gut tells me that its unnecessary but I'd just like to learn more about it to make a more informed recommendation.