After Microsoft's pre-E3 press conference yesterday, we got our first chance to try out Project Xcloud, the cloud-based streaming gaming service the company will be launching in October. Video analysis of those hands-on tests shows response times via Wi-Fi that are practically indistinguishable from local gameplay—at least for a streaming version of Halo 5. For something as sensitive to latency as a first-person shooter, seeing is believing.

We tried out Project Xcloud on a Samsung Galaxy S8, mounted to an Xbox One controller connected via USB. The game was running on the Microsoft Theater's Wi-Fi connection, but a Microsoft representative couldn't comment on the bandwidth or other details of that connection.

Playing Halo 5 on that setup felt responsive to my fingers, running at an apparent 60fps. We didn't have a high-end, custom-built latency testing rig to measure things precisely. But we did have an iPhone with a slow-motion camera to do some quick visual testing.

In our video tests, the time between tapping the A button and seeing a response on the smartphone screen took 16 frames of a 240fps video (or 67 milliseconds) across three subsequent tests. That's almost imperceptibly slower than the 63ms (milliseconds) input latency Digital Foundry measured on the Xbox One version of Halo 5 in 2017 tests.

Testing latency of a wired Google Stadia demonstration at March's Game Developers Conference, Digital Foundry found total latency of 166ms, compared to a low of 100ms on a 60fps PC.

We'll of course have to hold off a final assessment until we can try out Xcloud on our home networks on a variety of different games (and comparisons against those games running locally). For now, though, this early test in ideal conditions shows that responsive streaming gaming should at least be possible.