Update: Alas, Apple has told the developers of f.lux that they can’t distribute f.lux outside the App store, either.
There’s been a lot of talk lately about how blue light late at night can mess up your sleep cycles. I even know people who wear amber goggles at night to block out the blue wavelengths that are thought to cause sleep issues.
What would be better than wearing an orange eyeshade? Software that senses when it’s getting close to bedtime and adjusts the color your smartphone, tablet, or computer display to output less blue light. The most frequently recommended software to do this is called f.lux and is available for Mac, Windows, Android, and iOS.
There’s just one problem: f.lux can’t be in the App Store because the way it changes the display of your iOS device’s screen uses features of the operating system that Apple reserves for itself. Here’s hoping that iOS 10 might offer a feature that makes f.lux unnecessary, but in the meantime the only way to use f.lux on iOS has been to jailbreak your devices and download it from the Cydia store.
Well, I’m not willing to jailbreak my devices, for reasons of both convenience and security. Fortunately, the makers of f.lux have decided to offer an alternative path to get f.lux on devices without jailbreaking—they’ve released the app as an Xcode project so you can install it on your devices yourself.
To do this, you’ll need a free copy of the Xcode developer tools and a developer account . The f.lux website provides step-by-step instructions on how to load the app onto your device.
One major caveat: In addition to this being a nontrivial installation process, you’re foregoing Apple’s usual App Store scrutiny for this one app. You’ve got to trust the f.lux developers. If you’re not comfortable with that, look away—preferably at something that’s not putting out bright blue wavelengths.
[Hat tip: Alberto Sendra.]