Google, Tesla, Ford, Toyota, GM, Volkswagon could have a new competitor to deal with if rumours of Apple’s smart car plans are true.

Tesla’s CEO Elon Musk said that Apple’s car development is an "open secret" hard to keep, he told the BBC.

Apple has never confirmed or denied it is working on a smart car. However, Tim Cook’s company has this week registered domains allusive to a car manufactured by the company itself. The company has acquired apple.car, apple.cars and apple.auto.

The news Apple is developing a smart car took traction after reports from August 2015 revealed a secret visit by the company’s CEO Tim Cook to BMW’s headquarters in Germany in 2014.

Adding to this, at the time The Guardian also obtained a letter that revealed the iPhone maker was looking for a test location for cars in the Silicon Valley area.

Musk, who recently launched its newest and smartest car to date, Tesla X, said that it is "obvious" that Apple would tap into the automotive race. He said: "It is pretty hard to hide something if you hire over a thousand engineers to do it."

As for Tesla, the CEO does not believe the Cupertino-based firm is a threat. "It will expand the industry," he said. "Tesla will still aspire to make the most compelling electric vehicles, and that would be our goal, while at the same helping other companies to make electric cars as well."

Musk’s Apple remarks have not been the only big news around smart IoT cars in the last 24 hours.

GM, which expects to have 12 million connected cars on the road by the end of 2016, has launched a program inviting hackers to find security bugs and/vulnerabilities in its products.

The company wants hackers to report back to them if they find any flaws through its new HackerOne portal, a San Francisco start-up GM is backing to answer its needs.

Jeff Massimilla, GM’s cybersecurity chief , said: "We are putting a lot of technology into our cars. There is a responsibility obviously to put an appropriate level of security with those technologies."

American automaker Ford has also continued to unveil its projects in the smart car space since its major announcements at CES last week.

Yesterday, the company said it will be testing driverless vehicles in several weather conditions, including when the road is covered with fog, sleet and snow.

The tests will look at how LIDAR systems, which uses cameras that constantly track if the car is not driving off the road, cope with such elements. The LIDAR system will also work with Ford’s own 3D maps.

Ford expects ten million of its cars to have 4G LTE network connectivity by AT&T by 2020.

Lastly, in China, car maker Baic has said that it will allow customers to drive driverless cars that are manoeuvring around each other in a first of its kind in the automotive industry. The firm will be rolling-out ten electric vehicles later this year.