Sure, but to most developers the functionality of seeing their mobile application running on their desktop machine is "emulation". And they probably don't need true emulation, they just need to test their application
As an iOS developer that seems like a moot point. There are device bugs that cannot be replicate in the simulator, but everyone knows that. That's why you need devices.
But for general everyday development, I much prefer the simulator - I can look at the result of a code change in under 5 seconds with a simple keystroke, and not even have to pick up a device off my desk. It's empowering to be able to tweak your UIs and see the results in almost-real-time. I cannot do that if I'm forced to push the app to devices every single time.
Not to mention the debugger runs a hell of a lot faster on the host machine than any device - for the vast majority of bugs that isn't based on device quirks, it makes them much quicker to isolate and resolve.
Sure my point is that this article is mistitled. They're not increasing the emulator speed 400%, they're switching to Android x86 and achieving speed ups. This may be a good thing to do but is entirely different from improving the speed of the emulator itself.
