App developers hide away some debug menus in their apps, that are more relevant to themselves for testing and of not much use to you, the end user. However, you could find them interesting quite often.

If you got root access, you cna enable the debugging options on such apps, using the DebugEnabler Android App. While it should work great with all Google Apps (Play Store, Hangouts, Messenger, Google Fit, Play Books, etc.), the non-Google Android apps should work too — provided there is a debugging settings stacked inside the app.

Download DebugEnabler App from play store.

To use, install the app from above link, open, and provide root permissions. Then use the toggle to enable or disable app’s debugging settings.