Screen readers are often used by people with blindness or low vision to navigate apps. Use Narrator to test the screen reading experience of your app. Starting with the Windows 10 Anniversary Update (build 1607), we introduced a new developer mode in Narrator. When developer mode is enabled, the screen will be masked and will highlight only the accessible objects and the associated text that is exposed programmatically to Narrator. This gives a you a good visual representation of the information that is exposed to Narrator.