A few people have been talking about Sword&Poker, but I thought I'd give a bit more detail, since I have spent a lot of time with it now (probably half way through).
Appshopper link:
99c on special.
It's a weird meld of a card placing game to make poker hands, and an RPG.
As bjork mentioned, it's a basic dungeon map broken up into 'floors'. Each floor has a series of predetermined paths with monsters (the monsters are also predetermined), and your aim is to get to the exit to the next floor. The maps never get very intricate, and normally just give you an fork if you want to get extra treasure. You can only heal using 'charges', which you are typically given one per floor (doesn't roll over, although some rewards are more charges). So the choice is basically risk death (meaning you have to start the floor again) for more loot.
The actual battles are played out one on one on a 5x5 grid. 9 cards are randomly placed from the deck into the centre slots. Starting with you, you are dealt 4 cards, and have to place two down to complete a poker hand either horizontal, vertical, or diagonal, and you have to use the cards in the middle. You must score at least a pair. You do damage according to the type of hand you make and the type of weapon you're using (see screen above for example). Each round of battle takes place in turn with the monster until the board is filled (and then cleared for the next round), or if ten turns are played (a pass counts as a turn).
The strategy isn't really about forming hands so much as trying to judge what the opponent will do with their cards. The biggest deal is near the end of each round where, if played correctly, you can fill the final diagonal slot and potential get 5 hands at once. The astute among you will realise for this to happen, you'll have to pass at least one turn (or have the computer pass a turn), as you always start. It plays out oddly at first, but you get the idea soon enough and realise that passing can be a risky affair, as you miss a turn in doing damage, and not necessarily guarantee that the computer won't try to use that slot (depending on how the board fills up, the last 2 or 3 turns have potential to finish 3 hands at once.
The strategy is never really that deep, but is engaging enough to keep you interested. Actually, I didn't like the game at first, and found the strategy to be lacking, and feeling bored due to not really 'getting' it.
But it really does shine later on, mostly due to the weapons (special weapons available in a shop can afford the usual effects, such as absorbing life, paralysing, etc). A shield adds extra strategy to the timing, as it acts as extra hit points that get replenished every round (not just every battle).
On top of that there are magic spells that you can use once per battle (when you get them later on). YOu can arm yourself with a variety of spells which has effects like rearrange the centre cards, swap shields, steal cards and so on.
There's also a damage meter that builds with the amount of damage you've done, and when full, you can activate to turn one of your cards into a Joker (wild card), which is very powerful.
It's only 99c, supposedly down from $3.99 (it says 75% off), and is easily worth that. I recommend it and suggest that you give it a good solid go (get a few levels in, where you get some more items and stuff).
There's also a multiplayer mode, but I haven't tried that.
