This week, a blue-light reduction app called FlexBright, which works similar to Apple's own Night Shift mode or f.lux as the Jailbreak community knows it. Initially Apple approved the app, which was able to adjust the screen temperature for the entire iPhone, Apple pulled it from the App Store.

The developer of Flexbright, Sam Al-Jamal told sources that he had worked with Apple through several app rejections to get FlexBright into the App Store and that no private APIs were in use, something that was seemingly confirmed by the app's approval, but further review from Apple led to FlexBright's removal. Al-Jamal has shared Apple's explanation with MacRumors following an "exhausting discussion" with the Cupertino company. "
The FlexBright app adjusted the temperature of the screen to make it more yellow, like Night Shift in iOS 9.3
I recreated three classes based on non-public APIs. Even though these are custom classes that I created, but essentially they're using the same methods as in their non-public APIs.
We labelled it as a new feature to "rest/close your eyes for few minutes and listen to some music". Now Apple says this is not the intended purpose of the app and they won't allow this approach.
Al-Jamal (developer) behind FlexBright was using some questionable features to get the app to function, but its ability to slip past the App Store review process even through multiple rejections again puts a spotlight on Apple's inconsistencies and failures when it comes to reviewing apps which has happened previously.
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