I am getting 2 Lumia 520, how is the app thing ? And your 520 experience?

So I have been using a Blackberry Curve for the past month after by lovely HTC Wildfire gave up it's life. After much consideration, I decided to order 2 Lumia 520'S yesterday. I debated with my self a bit about getting a low budget Android phone with LG in mind but after seeing how laggy most of them are, i'm talking about one of the Optimus LGs I played with, I decided to go Windows Phone. I have a Galaxy tab and will get the Note 3 when it comes so I like using every platform, I have no interest in tying myself to one ecosystem, oh I have iPod touch and iPad for my IOS needs as well as well :). Now to the question, how is the app situation on the Lumia 520? I read a review yesterday which says there are only 20 games playable in the Windows Store on the 520, is that true? I don't care about any other app but I want my DH Poker or any Poker online games. For others, the only Google service I use is Youtube and my tablet takes care of that so i'm sorted but kindly advise me on the apps you think I might need from the Windows store to make my Lumia 520 experience a pleasant one. A friend also said Windows Phone because of the live tiles are a data hog, how can I control data usage of the phone? By the way, what sold me was offline navigation and map access, Nokia's suites as well as the smooth performance of Windows Phone 8. The lack of flash is annoying for me though but how is you experience and every day use of the Lumia 520?