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Thanks for the detailed answer, I did wonder what the exact reason was. Do you think there would be much overhead - financially speaking - speaking to adding the dedicated hardware? I ask because I can only see them doing it if it's financially viable, as in, will enough disabled people or those interested in voice recognition by the iPhone to make it worth our while. Also, does the CPU get hot whilst it's plugged in…
I doubt the CPU gets too hot. We're talking about something like 5% utilization. There's a pretty large difference in power consumption between a constant 5% and zero, but there's also a pretty large difference between 5% and 100%. If you run an iPhone at full blast it'll last a few hours before the battery dies. If it's completely asleep then it'll last days. Constant listening would probably cut the standby time do…
I wonder if it would be possible to use that dedicated audio playback hardware for this purpose, I would definitely pay a relatively small sum towards RND if anybody is interested!
I also wonder if there's a worry that average users might turn this on accidentally, running their battery out and then shouting at Apple? If that's the case, it could be happily buried in the Accessibility menu I think. Seriously, this feature would enable me to keep my iPhone in my top pocket while I go out and be able to access Siri rather than cart about all the other equipment. It would be great!
Edit: Why isn't accessibility in Dragon's menu?!