An application named FlexBright has been approved by Apple today in the appstore, the appallows you to manually adjust the display's color temperature of your iPhone or iPad. That makes this one of the first third-party apps to make it into the App Store that provides a feature similar to iOS 9.3’s Night Shift mode.

It's funny that Apple would green-light a title like FlexBright, for those who aren’t familiar with the story, last fall the iPhone-maker asked the developers of f.lux—a long-running app with similar functionality to FlexBright—to shutdown their iOS work.
The way FlexBright works is a little bit different, though. The application runs in the background on your iOS device, and sends you a notification prompting you to change the temperature settings on your display based on either the time of day, or by custom times you assign.
FlexBright has a smart calculator that monitors your exposure to blue light throughout the day and will alert if you if eye fatigue is detected. Put in your bedtime and FlexBright will monitor your exposure to blue light and alert you to reduce brightness when it gets closer to your bedtime to minimize blue light effect on your sleep cycle.
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