Disklavier

I've done some searching around the forum, but haven't found exactly what I'm looking for, so I hope someone can answer these questions, or point me to the answers that are undoubtedly here somewhere. 

I have an 11-year-old DC3A with the original DKC55RCD controller. I've just moved it into my new wife's home and would like to be able to control it remotely from a desktop computer and/or other wireless devices. 

In my old home, the Disklavier was connected via MIDI to my laptop, and when I was so inclined I could control it from my home office with a remote viewing program that took control of the laptop from my office desktop. It was cumbersome, and I didn't use it often, so I'm not inclined to go back to a similar setup.

That was years ago, and I'm hoping there are newer and better ways to do it now. 

My primary interest is the ability to play standard MIDI files and playlists that would be stored on the network. Playing PianoSoft files or other special formats is not a top priority. I have zero interest in Yamaha's Internet Radio service, but might have slight interest in a similar service that was free. However, an Internet connection just for that purpose is not a high priority.  

I know about the DKC-850, and I'm considering it, but it seems a little pricey for what I'm hoping to do.  

Here are my questions: 

1. Is there a way, using the DKC55RCD, to play MIDI files and playlists using a networked desktop, laptop, tablet, and/or smart phone? We have an iPad, an Android smartphone (Droid 3), and plan to get an Android tablet. It would be nice if there were apps for both OSes, but since we have both we could live with one or the other if we had to. Android is my preference.

2. If the answer to #1 is no, or not easily or cheaply, does the DKC-850 definitely allow this? I've read through the literature and many posts, but it's not clear to me that this is is one of its capabilities. The brochures say a lot of the Internet Radio, but not so much about controlling the piano from other devices. 

3. If I get a DKC-850, does it need to be calibrated to my piano? Is this something I can do myself, or does it require a technician visit? 

4. If I don't get a new controller, should I re-calibrate the DKC55RCD after having moved the piano? Again, can I do it myself? And is calibration best done before or after tuning?

Thanks for your advice.