I have just started playing with these, but they are good and have great potential to play with. So far I've tried Funfetti and Spice cake mixes. I think the spice would be good if you added some apple chunks to it. I've also heard of adding chocolate chips but haven't tried it yet.
1 box cake mix
1/3 c oil
dash of water (if needed)
Mix ingredients together until moist. Drop onto cookie sheets like regular cookies. Bake at 350' for 10-12 minutes.