We put Siri, Alexa, Google Assistant, and Cortana through a marathon of tests to see who's winning the virtual assistant race - here's what we found

As the Amazon Echo continues to be a runaway hit, all the big players are convinced that talking to an AI will soon become the dominant way we interact with our computers.

So they've started building. Apple has Siri, Amazon has Alexa, Microsoft has Cortana, and Google has the new and refreshed Google Assistant.

The tech has come a long way, but all of these companies openly admit that it's very early days for this proposed future. As such, all of these assistants are far from polished.

But which one works best? I strapped in for 8 hours of robot conversations to find out, testing each of the big four assistants across a variety of categories. Here's how it went: