I work for a company that develops phone apps for the hearing and visually impaired. We are currently in the final stages of releasing a new app for visually impaired people, but have ran into a critical problem: During a (Call Kit registered) phone call, video chat mode, if voice-over is on, the screen will turn black when the proximity sensor is covered e.g. by the user’s fingers. And when the screen turns black, the connection to the user’s braille board is also lost. Why does the iPhone behave this way? When voice-over is off and with loud speakers on, the screen will never go black even when the proximity sensor is covered. Why cannot iPhone behave this way when voice-over is on? Or is there a workaround we haven’t thought about? I recognize that we are not the only ones having run into this issue. For example, there is a post on StackOverflow describing the exact same problem: https://stackoverflow.com/q/59177195/650012 . Unfortunately the responders to that question have not recognized that the issue is related to voice-over use, and thus their suggestions are of no help.