Using ternary for if else

For the inside if:

if APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc {
   theImage.contentMode = .scaleAspectFill
} else {
   theImage.contentMode = .scaleToFill
}

Gives:

theImage.contentMode = (APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc) ? . scaleAspectFill : . scaleToFill

Now, if we do the top level if:

theImage.contentMode = UIDevice.current.iPad ? insideIf : . scaleAspectFill

In full code:

theImage.contentMode = UIDevice.current.iPad ? (APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc) ? . scaleAspectFill 
                                                                                                                                    : . scaleToFill 
                                             : . scaleAspectFill

That's not really redable.

But

if UIDevice.current.iPad {
    if APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc {
        theImage.contentMode = .scaleAspectFill
    } else {
        theImage.contentMode = .scaleToFill
    }
} else {
    theImage.contentMode = .scaleAspectFill
}

Might be transformed into:

if UIDevice.current.iPad && !(APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc) {
    theImage.contentMode = .scaleToFill
} else {
    theImage.contentMode = .scaleAspectFill
}

That's shorter, but might be harder to read.

With ternary if:

theImage.contentMode = UIDevice.current.iPad && !(APIClient.shared.whiteLabel == .gld_default || APIClient.shared.whiteLabel == .abc) ? . scaleToFill : . scaleAspectFill

In my opinion? Keep your version (or maybe the version where I use only one if/else). Compiler will optimise nevertheless, and it's easier to fix/modify it two months later if you can grasp why and what it does quickly.