iPhone like Alphatrack: which app?

Just starting to investigate the world of WiFi MIDI control. I'm confused by the threads: touchosc, novation, ac-7, reaper_www, etc. I'd like to replicate the functionality of the Alphatrack. Just a fader, pan control, maybe a send, maybe more? However, I don't think I need a transport. This would just be to replace the mouse when writing automation. Any recommendations on where to start? I'm not at all afraid of diving into the setup aspects. I just want to make sure I have the best starting point. Thanks!

Just dove into AC-7 Core Mini (Windows) 

Holy crap. Totally easy to get up and running. The iPhone screen is so small. The fader responses are reliant on some pretty precise finger movements (not like grabbing a fader). Wish there would be a fader that runs the length of the screen (instead of the width). Still have to put it through a practical use situation. Anyway, a very fun 20 minutes on a Sunday night! (got it running in PT as well)