While Android Lollipop added a flashlight toggle into Quick Settings, circumventing most third-party torch apps, the function was only accessible in the notification drop-down and as an on/off switch. If you wanted to use the flashlight with morse code, for signaling, or other patterns, you still had to use a separate application and developers of said apps didn't have any clear API to build their software on. They had to hack together solutions for various phones, relying on whatever way the different OEMs had created to access the camera's flash.

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