I'm a Quadriplegic-what's the best phone for voice control?

So like the title says, what is the best phone to get if I'm going to use voice control? While Siri is impressive I have dabbled around with my Mom's Samsung S4 and I thought that was pretty impressive too. But are certain Android phones better than others?

Also, are there any other good applications out there that might help me? Basically I'd like to be able to answer calls, and calls, send and receive text messages/emails and… I'm not sure what else but I do have a stylus that I use to control my iPad with.

So with all of that said, what are your suggestions and recommendations? I really appreciate all the help and look forward to hearing your suggests!

Cheers,