Documents from Apple show the iWatch maker is potentially developing an autonomous IoT car and looking for test locations in Silicon Valley.

Correspondence between Apple engineer Frank Fearon and Californian car testing facility GoMentum Station, has revealed that Apple is looking for a location to test a smart car.

In the letter obtained by The Guardian it reads: "We would … like to get an understanding of timing and availability for the space, and how we would need to coordinate around other parties who would be using [it]."

The GoMentum Station is half an hour away from San Francisco and was designed for driverless car solutions to be tested, according to the BBC.

Fearon also wrote: "We are hoping to see a presentation on the … testing grounds with a layout, photos, and a description of how the various areas of the grounds could be used."

Following Apple CEO Tim Cook’s surprise visit to BMW last year, rumours have grown surrounding Apple’s involvement in the development of a self-driving vehicle.

The race to develop the ultimate smart driverless vehicle is gathering pace between Google and Apple.

Matthew Hunt, CEO at Apadmi Enterprise, told CBR: "Google is very much leading the way in its innovation, but rumour has it that Apple is now teaming up with a high-profile car manufacturer to compete in the race to create the ultimate smart car.

"For Apple to be able to catch up with Google, or even overtake Google’s offering, it’s going to have to come up with something unique that really challenges Google’s project.

"Google has been publically working on its version for many years, so in order for Apple to come in and shake up the competition it needs to think quickly and innovatively to create smart car software that offers something that the Google smart car won’t be able to."

However, some experts also believe the two firms could become strong partners in the smart car space.

Dr John Bates, CMO at Software AG, told CBR: "[In the US] industry Titans can be effective partners, with Google and Apple both exploring connected cars. Google is testing a self-driving car that uses detection technologies such as radar, sonar devices, stereo cameras and lasers.

"With prototype projects starting now, self-driving cars will evolve to become mainstream in 10 years, along with prototype smart cities."