You can tap the full screen icon () on the right of the titlebar to view the application in full screen (without the titlebar) at runtime, as shown in the following figure.
Tap the normal view icon () on the top right corner of the window to return to the normal view (with the titlebar visible).
If the App Titlebar option under General is turned off (it is turned on by default), the application will run without the titlebar as it is opened, just like the full screen view.