F.lux is an app that that adjusts your screen’s brightness at night to cut down the blue light that keeps you awake. Sound familiar? That’s because Apple just put the same exact feature in iOS 9.3. F.lux briefly offered a version for iOS last year, but the app is only available for Mac, Linux, and Windows because Apple told the developers to shut it down. F.lux’s creators are now asking Apple to reverse its decision and let the app back in.
Apple calls its version of F.lux Night Shift. F.lux’s developers penned a blog post after news of the iOS 9.3 feature emerged, praising Apple for acknowledging the health risks of exposure to bright blue light at night, but also taking a stand for their own work on the science of sleep.
“Apple’s involvement in fixing this problem is a big commitment and an important first step,” developers Michael and Lorna Herf wrote. “We’re proud that we are the original innovators and leaders in this area. In our continued work over the last seven years, we have learned how complicated people actually are. The next phase of f.lux is something we cannot wait to ship to the world.”
The story behind the story: The Herfs have asked Apple to open up a public API for Night Shift, an optional feature which warms up the light on your iPhone or iPad screen at sunset and returns it to normal at sunrise. F.lux was never available in the App Store because it called a private API—no public one was available. So the Herfs allowed people to sideload the app using Xcode until Apple laid down the law.
Apple hasn’t yet responded to the F.lux request. To give Night Shift a shot in the iOS 9.3 public beta, go to Settings > Display & Brightness, then toggle on the Blue Light Reduction option. You can allow the feature to automatically adjust your screen’s light at sunset and sunrise, or you can customize your schedule.