Related: Here is an interesting piece from Benedict Evans, where he argues that there are currently many reasons voice technology isn't ready to be the next platform.
http://ben-evans.com/benedictevans/2017/2/22/voice-and-the-u...
An excerpt:
"There's a set of contradictions here, I think. Voice UIs look, conceptually, like much more unrestricted and general purpose interfaces than a smartphone, but they're actually narrower and more single-purpose. They look like less friction than pulling out your phone, unlocking it, loading an app and so on, and they are - but only if you've shifted your mental model. They look like the future beyond smartphones, but in their (necessarily) closed, locked-down nature they also look a lot like feature phones or carrier decks. And they're a platform, but one that might get worse the bigger the developer ecosystem"