HTC shows you how to enable Night Mode on the HTC U Ultra
Remember the Android 7.0 feature Night Mode? This was supposed to give Android users the ability to remove blue light on the display, giving the screen an amber look. Without the blue light coming from the screen, users might find it easier to fall asleep since that light can negatively impact users' life cycles. In addition, removing the blue light makes the screen "warmer," and that also will help users get to sleep without a problem.
However, it would appear that the recently unveiled HTC U Ultra will offer Night Mode right out of the box. A video released by HTC shows how U Ultra users (love that alliteration) can enable the feature. Scrolling down on the notification bar will allow them to tap on the icon; if you look closely at the video, the screen turn amber instantly. Users can also customize Night Move to turn on at a certain time and also turn off at a certain time. To do that, go to Settings > Display, gestures and buttons and click on Night Mode.
source: HTC
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