Until now, Google and Uber have been pretty cosy. Some would argue, too cosy: Uber is the only third-party app linked with Google Maps, and Google Ventures is one of Uber’s biggest investors.

This week, though, each has done something to stamp on the others’ toes. From TechCrunch:

Driver-on-demand service Uber is building a robotics research lab in Pittsburgh, PA to “kickstart autonomous taxi fleet development,” sources close to the decision have confirmed. 

Meanwhile, from Bloomberg:

Google is preparing to offer its own ride-hailing service, most likely in conjunction with its long-in-development driverless car project… Uber executives have seen screenshots of what appears to be a Google ride-sharing app that is currently being used by Google employees. 

Uh oh. 

Both companies are fervently seeking the transport holy grail: self-driving taxis, summoned by app. Until now, each company held half the equation, but now it seems they’ll be direct competitors, rather than partners.

Google probably has the upper hand here: their self-driving cars may not be ready until 2017, but they’ve put in a fair amount of investment already, and designing a transport app isn’t going to pose much of a challenge for one for the largest technology companies in the world.

Uber, meanwhile, has signed itself up to develop a far more complex technology which is still in its infancy. They may have snapped up 50 scientists and robotics engineers from Carnegie Mellon University, but it seems highly unlikely their research will outflank Google’s. 

Let the games begin.