A Notification LED is a small RGB or monochrome LED light usually present on the front-facing screen bezel (display side) of smartphones and feature phones whose purpose is to blink or pulse to notify the phone user of missed calls, incoming SMS messages, notifications from other apps, low battery warning, etc., and optionally to facilitate locating the mobile phone in darkness. Versus: For and against LED notification lights in phonesHow to customize notification LED behaviour on Android - BeeBom.com It usually pulses in a continuous way to draw the attention of the user. It is a part of the device's notification system that uses a cloud-powered push notification service to relay remote notification messages to the user, or local notifications. Similar to audio notifications, a notification LED is a very battery-efficient way to inform the user of new notifications without turning on the screen at all.
Overview In any mobile phone or smartphone, battery life is an important consideration and the display is the component that consumes the maximum battery when it is fully lit up. In regular usage, a user may only want to briefly turn on their phone to check if anything requires attention.
By blinking unobtrusively, the notification LED light discreetly conveys to the user of any potentially important message or call. Customize Your Android Phone's Colored LED Notification Light This way, the whole display does not have to be turned on every time a message arrives, thus saving the battery. When the user is away from the phone or when the phone is in silent mode, the blinking LED can effectively convey the user that some action is needed. Conversely, if the light does not blink, then it conveys to the user that there is no unread message or notification that requires their attention, again saving battery and the user's time and effort required to unlock the device, and check for new messages.
In some phones, the LED notification light is also sometimes designed to glow red when the battery is low, when the battery is charging and turn green when the battery is fully charged. This saves the user the hassle of turning on the screen to check the battery percentage.
While most phones used to include the notification LED light on the front side, some smartphone manufacturers like LG or Nokia also integrated it into the power button, HMD Global patents power button notification LED while some phones from Motorola, Xiaomi, Razer or ASUS had their brand logo on the back side of the phone, serving as the notification light. Latest Motorola One Zoom renders reveal unique light-up rear logo
Depreciation Starting 2019 most smartphones vendors have stopped adding the notification LED which could be explained by the advent of AOD and a drive for smaller bezels.
Customization based on app In some Android and BlackBerry smartphones, the notification LED light's behavior could be customized per app, so that, each color would indicate a different app. Apps like WhatsApp or Telegram also include a setting to set this color for the LED light.
Alternative always on display feature
The notification LED light was popular when feature phones were widely used. In early smartphones running Windows Mobile or the Android operating system, the LED notification light was also a fairly common feature. These smartphones usually had LCD screens, so without the LED present, the entire backlight behind the display would need to be turned on to check for any new notifications.
Gradually, the smartphone industry has been moving towards OLED displays. With this transition, the dedicated notification LED light has slowly been eliminated from newer smartphones. There is also a focus by smartphone designers to minimize the screen bezels or keep them very thin, thus leaving no room for the notification LED light.
As a replacement for the LED light, some smartphones from Samsung, LG, and Nokia include an Always On Display feature. On OLED displays, the Always-On Display (AOD) shows limited information while the phone is asleep, that is, when the entire display is not lit up. With OLED screens, only a part of the screen, or a few pixels on it can be turned on to convey information.
With any pixel on an OLED screen effectively being a notification LED, software can be used to customize its appearance. It can blink or pulse like a light continuously, or some phone manufacturers light up the display's pixels like a ring or have edge lighting.
+Smartphones with Notification LEDs (since 2017)ManufacturerModelYearLED PositionLED ColorNotesLibrem52020Front TopRGBOnePlus52017Front TopRGBOnePlus5t2017Front TopRGBOnePlus62018Front TopRGBLast OnePlus model with Notification LEDSamsungGalaxy J82018??SonyXperia 12019Front TopRGBSonyXperia 1 II2020Front TopRGBSonyXperia 1 III2021Front TopRGBSonyXperia 1 IV2022Front TopRGBLast Xperia 1 series with Notification LEDSonyXperia 52019Front TopRGBSonyXperia 5 II2020Front TopRGBSonyXperia 5 III2021Front TopRGBSony Xperia 5 IV2022Front TopRGBLast Sony Xperia 5 series with Notification LEDSonyXperia 102019Front TopRGBSonyXperia 10 II2020Front TopRGBSonyXperia 10 III2021Front TopRGBSonyXperia 10 IV2022Front TopRGBLast Sony Xperia 10 series with Notification LEDSonyXperia L32019Front TopRGBSonyXperia XZ Premium2017Front TopRGBSonyXperia XZ12017Front TopRGBSony Xperia XZ2 series2018Front TopRGBSonyXperia XZs2017Front TopRGBSonyXperia 82019Front TopRGBSonyXperia L42020Front TopRGBXiaomiRedmi Note 92020Front Top?Also on various related modelsXiaomiRedmi Note 72019??SamsungGalaxy S8 series2017Front TopRGBSamsungGalaxy S9 series2018Front TopRGBLast Samsung flagship smartphone with Notification LEDSamsungGalaxy Note 82017Front TopRGBSamsungGalaxy Note 92018Front TopRGBLast Samsung phablet with Notification LEDBlackBerryKey12017Front TopRGBBlackBerryKey22018Front TopRGBBlackBerryMotion2017Front TopRGBOppoReno 7 Pro2021Rear TopBlueMotorolaMoto G7 series2019Front TopRGBMay need 3rd party S/W to enable. May be sub-model distinctions.MotorolaMoto Z32018Front Top?May need 3rd party S/W to enable. MotorolaMoto G5 series2017Front Top?May need 3rd party S/W to enable. May be sub-model distinctions.Nokia3.22019Side buttonWhiteOverlaid with power button, white color only.Nokia4.22019Side buttonWhiteOverlaid with power button, white color only.XiaomiRedmi K502022Rear?Includes variants eg Poco F4 GT etc. Some are in camera module.ASUSZenfone 82021Bottom EdgeSimple colorReputedly only supports red, green and yellowXiaomiMi 10T Pro2020Front, Top LeftWhiteHuaweiY6 (2018)2018Front, Top LeftRGBThe phone uses Red, White, and Green (follows battery level) for generic notifications. Otherwise, the phone follows the LED color that the app uses.XiaomiPocophone F12018Front, BottomWhite
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