There is a segment of the avionics industry that isn't regulated. Experimental aircraft. I speak (honestly I'm typing, but if you wanted I could read this whole comment out loud) from a position of some knowledge on this. I am a commercial pilot and a flight instructor and am also building my own experimental aircraft. (Go Velocity! - http://www.velocityaircraft.com/
A TSO'd two panel glass avionics display consisting of about 8 to 10 inch PFD (Primary Flight Display) and MFD (Multi-Functional Display) will cost you in the neighborhood of $70,000 for a certificated system. (http://www.avidyne.com/products/release-9/r9-cirrus.asp)
An experimental setup with similar capabilities can be had for perhaps $15,000. (http://www.dynonavionics.com/ http://www.grtavionics.com/ )
While I may personally think that the FAA has been overly cautious about allowing unknown devices on commercial flights, I would like to point out two things:
First, their goal is to make things SAFE. Not comfortable. Not convenient. Not mobile-app-enabled. Safe. And they have done a heck of a job of that. Look at the safety record of the commercial aviation industry in the US. It's incredible. More people die on the way to or from the airport than die after they get there.
Second, if device manufacturers wanted to pony up the cash to certify their devices they could. If Apple, Samsung and Motorola really wanted to they could pay to have their devices certified. But it's easier to simply blame the FAA. There is no budget in the FAA for certifying these devices. If they spent the money on this instead of other things the accident rate would go up. What do you think is the right choice for an organization whose goal is to make aviation safe?