Hmm....I don't know what you actually saw there, TC. It's a beautiful scene, but if that's a picture of deer, I think you needed another cup of coffee or something.

I can't see deer in there, no matter what I do.
I think you did a good job improving the color and contrast. As others have said, you can't bring out detail that isn't there. You can, however play around with low-quality images and come up with some interesting--if not always realistic--results. I'll bet you didn't see this:

I don't know what controls, if any, you have on your iPhone. I agree with WTFH that the blank white sky threw off your exposure. If you can "lock" the exposure somehow, next time try aiming only at the green grass, locking in that exposure, then re-framing the picture as you like it. (On many point-and-shoot cameras, you can lock the exposure by pressing the shutter release button down half way, and holding it there as you re-frame. Don't know if that's possible on the iPhone.) If you cannot lock in exposure, then try framing with less sky, as WTFH suggests.
Does the iPhone have a "backlight" compensation setting? Or a "snow/sand" setting? Or anything like that that is meant to improve the exposure of a scene where a bright background throws it off? You can try these. One great thing about any digital camera is that it doesn't cost anything to experiment.
Good luck!
Best regards,
Bob