The newly introduced iOS 9 Facedown feature is available to only some iPhone owners. If you have the older iPhone 4s or iPhone 5 model that is supported by iOS 9 firmware you will upset to learn that iPhone detect fact down option is not working on your smartphone. This is an interesting options created by Apple in order preserve your battery life. When you place the handset face down on the table or other surface its screen will stay dark and never light up even when you receive a phone call, text message or notifications. This iOS 9 face down feature is a part of the battery-saving plan. Are you curious to hear why the two versions of Apple smartphones with proximity sensors and ambient light are not supported by facedown technology? According to Apple, its new iOS 9 Facedown detection relies on the motion coprocessor that is present in models starting with iPhone 5s. This means that unfortunately two older versions, iPhone 5 and 4s that don’t have the M-series motion coprocessor, cannot support the new feature because its coproccessor cannot collect sensor data from CPU cycles. If Apple allowed these two models to get information from the main CPU it would quickly drain the battery and the whole purpose of the battery-saving option would be useless. It is curious that iPad users are not able to get the features even though they have the required motion coprocessor. It happens because all tablet devices that are running iOS 9 firmware version come without the proximity sensors. Users with iPod touch also cannot benefit from the iOS 9 update because their gadgets have not proximity sensors as well as ambient light. As for iPhone 5S, 5c, 6, 6 Plus and upcoming iPhone 6s and 6s Plus users, they cannot turn off iOS 9 facedown detection option directly.