Flash is a new tweak available since last night in Cydia for iPhones running iOS 9, it being specially designed to automatically display a button in the LockScreen that enables the activation of the camera's LED flash to turn an iPhone into a flashlight.
More specifically, Flash it uses the ambient light sensor of our iPhones to realize if a room is too dark for us to see what is inside it and when it detects the dark area it displays a yellow button that allows the activation of the LED flash, the image above showing the functionality.
Compatible with iOS 8 and 9. Flash intelligently uses the ambient light sensor built-in your device to provide a button to invoke the LED flash when it is dark. This button appears in the bottom left of the lock screen, exactly where a Siri suggested or handoff app would be.
Flash is available for download from Cydia's BigBoss repo following this link.
