How to turn on flash light in iOS

 - (void) setTorchOn:(BOOL)isOn

{

    AVCaptureDevice* device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    [device lockForConfiguration:nil]; //you must lock before setting torch mode

    [device setTorchMode:isOn ? AVCaptureTorchModeOn : AVCaptureTorchModeOff];

    [device unlockForConfiguration];

}

Pass a bool value to above method.

If we pass YES then the flash light will glow.

EXE: [self setTorchOn:YES];

If we pass NO then the flash light will stop glowing.

EXE: [self setTorchOn:NO];