Completed next tasks:
5. Drag out a switch (UISwitch) or a segmented control (UISegmentedControl) into your View somewhere which controls whether the game matches two cards at a time or three cards at a time (i.e. it sets “2-card-match mode” vs. “3-card-match mode”). Give the user appropriate points depending on how difficult the match is to accomplish.6. Disable the game play mode control (i.e. the UISwitch or UISegmentedControl from Required Task #5) when flipping starts and re-enable it when a re-deal happens (i.e. the Deal button is pressed).
Added last task:
7. Make the back of the card be an image (UIImage) rather than an Apple logo.

Had to prepare a transparent image for UIControlStateSelected, otherwise, if set to nil it uses the image in the Normal state
Possible workaround - swap Normal and Selected states.