An always-on display (AOD) is a smartphone feature that has the device continue to show limited information while the phone is asleep. It is widely available on Android handsets, and is available on Apple iPhones since the iPhone 14 Pro. On some Android devices, the feature is sometimes called Ambient Display or Active Display, depending on its implementation and behavior. Depending on the phone's design, it may be a replacement or complementary to another feature, such as the notification LED. Overview A device with AOD enabled keeps a limited portion of the screen on during sleep mode. An Always On Display may display a set of recent push notifications in place of a notification tone or LED signal, as well as information such as the time, date, and battery status of the device; they often may also be configured to also show various types of notifications as they arrive, or screensavers. Various devices have differing behavior for this feature. Some phones would have the screen off until new notifications arrive whereupon the display would either be active for a few seconds or remain on until the user interacts with the device to read or dismiss the notification (essentially having the entire screen serve as a larger notification LED); others instead have the phone screen activate when it detects input, such as being picked up or the screen interacted with. These versions are often called ambient displays, in contrast to "true" always-on displays, where at least part of the screen remains on at all times. Again depending on the manufacturer, not all apps may be supported for showing notifications with this feature - only first-party apps or popular apps may be supported. History This technology was first introduced by Nokia in on the Nokia N70 and Nokia 6303 (on TFT display in 2008), and more widely adopted with its next generation AMOLED Symbian phones in 2010 (the Nokia N8, C7, C6-01 and E7). Later functionality was updated with Nokia Sleeping Screen app for last generation of Symbian smartphones (Nokia 808 and other) with features like custom standby screen from any image, and two themes for notifications design. It became a standard feature on most Nokia Lumia Windows Phones in 2013, paired with the Nokia Glance Screen app. The feature has since become more widely available on Android handsets. Apple has the feature since Apple Watch Series 5 (2019) and on iPhone