Choosing the right AVCaptureSessionPreset for different devices

Question

I am a little confused which preset I should use for different devices. Currently I am using AVCaptureSessionPresetMedium for all devices. However, I want to take a

Answer 1

#ifdef __AVAILABILITY_INTERNAL__IPHONE_9_0_DEP__IPHONE_9_0
CGFloat iOSVersion = [[[UIDevice currentDevice] systemVersion] integerValue];
if (iOSVersion>=9 && [session canSetSessionPreset:AVCaptureSessionPreset3840x2160]) {
    session.sessionPreset = AVCaptureSessionPreset3840x2160;
}
#else
// the code above won't compile in Xcode 6 and older
#endif

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