The "App platform" means it's a smart Blu-Ray player with access to the Samsung App Store. Netflix, Hulu Plus, etc.
I own this player, I got it from Cowboom a few months ago for $30, shipped. It works fine. I believe a majority of the problems with it are wi-fi related, which is fair. The wi-fi reception on this player is not great. 1 room / 1 wall away, and it only gets 3 bars out of my WD MyNet 900 router. Everything else in the same room gets 4-5 bars (more often 5). If the player was much further, I would expect to have issues with the connection.
Anyway, as a player it works great. As a smart device, it works okay. Not great, but okay.
Also, this Samsung BD player would play as well as any other Samsung device would with your Samsung TV and Samsung DVD 5.1 HTIB. Make sure to hook up the BD player with an HDMI cable to your TV and an optical cable either from your TV to your HTIB, or a coax cable directly from the BD player to the HTIB (depending on your setup).