OK, I bit the bullet and bought the 4 main craps games. THey were all $1 except Aw Craps was $2. Here's my initial thoughts on each after playing each for about 10-15 min.
Aw Craps - My favorite of the bunch. Very nice layout and graphics. Love the flick to roll the dice. Could use a bit better dice animation, but it works for me. Very realistic betting. You put your chips down, and then you call the bet. This makes betting a bit more tedious, but I like it. I also like that it shows you exactly how much you won or lost on each roll. Provides good info on each bet and what the payouts are. This one is a keeper.
Craps Deluxe - My 2nd favorite. Has lots of options, such as the option to ask you if you want to press your place bets after you hit the number. The graphics are simplistic and the layout is very compact. It has stickman calls, which is nice. No dice animation, the numbers roll like a slot machine. I don't like that it doesn't show you how much you won or lost on each roll.
Casino Craps - Has the nicest graphics and layout. No real dice animation, more like a slot machine where the numbers spin. Displays very quickly how much you won or lost on a roll for each bet, but you can tap on your bankroll to see the total amount won or lost. This is a more simple version, for example you can only place bets on numbers, you cannot buy numbers. You can only place C & E bets, you cannot buy each individually.
Craps University - This was ok, more of a tutorial and beginners guide. It's a bit too tedious to place bets since each bet it defaults to a certain amount and you have to manually add or decrease. The graphics are a bit weak and the layout is very compact. Just doesn't have the visual appeal of either Aw Craps or Casino Craps. I do like how the dice roll down the table, but you don't control the roll, just tap the dice to roll. I hate the explosion sound it makes when you lost a bet. For some reason I just didn't like this one as much. Great for beginners.