There's a bit of a Playdek sale till the 10th May. Looks like Agricola, nightfall, and summoner wars. With their expansions on sale too. Might be other games as well.
Talbs-how abstract is Agricola? Been thinking of buying it for the longest time but the game setting always had me putting it off.
I can tell you that it reeks of quality. Regardless if you're interested in the theme or not you can't help but appreciate how well it's done.
It took me quite some time to wrap my head around Agricola as to play well you have to think several steps ahead as well as dealing with other players possibly blocking those steps... It's a brilliant game with a lot of depth, but quite a bit of a learning curve. Easily worth the three bucks for the experience, I wouldn't worry about the expansion decks until you figure the game out a bit. Either find some other new players or prepare to be stomped by the AI quite a bit. If you'd like to play a game like this that is IMHO easier to play - take a look at Lords of Waterdeep, which is also very good on iOS.