In today’s Bulldog wrapup of technology and science news:

  • Google unveils video calling app
  • China launches a quantum satellite
  • Tesla Autopilot debate continues
  • More Apple shares for for Buffett

The details:

  • Google’s Duo app joins crowded field of video calling

Knock, knock, Google’s video chatting app has arrived.

The app, dubbed Duo, represents Google’s response to other popular video calling options, including Apple’s FaceTime, Microsoft’s Skype and Facebook’s Messenger app.

Duo isn’t much different from the other video chatting services, except that it gives a glimpse at who is making the call, helping the recipient decide whether to answer.Google calls this feature, “Knock, knock.”

The new app, announced in May, is being released Tuesday as a free service for phones running on Google’s Android operating system as well as Apple’s iPhones.

(Watch an introductory video atA; https://www.youtube.com/watch?v=E_0MZG-5E4U )

Like FaceTime for iPhones, Duo only requires a person’s phone number to connect. Many other services require both participants to have account logins to use their video calling options.

Google has been offering video calling through its Hangout feature for several years, but the internet company is now tailoring that service for business meetings.

Duo is being billed as a simpler, more reliable way to see friends and family as you talk to them.

It is the first of two new mobile apps that Google, owned by Alphabet Inc., has planned for this summer. The Mountain View, California, company also is preparing to unveil a new messaging app called Allo featuring a robotic assistant that will suggest automated responses to texts.

  • China’s launch of quantum satellite major step in space race

China’s launch of the first quantum satellite Tuesday will push forward efforts to develop the ability to send communications that can’t be penetrated by hackers, experts said.

The satellite launched into space from the Jiuquan launch base in northwestern China’s Gobi desert will allow Chinese researchers to transmit test messages between Beijing and northwestern China as well as other locations around the world.

If the tests are successful, China will take a major step toward building a worldwide network that can send messages that can’t be wiretapped or cracked through conventional methods.

“It moves the challenge for an eavesdropper to a different domain,” said Alexander Ling, principal investigator at the Centre for Quantum Technologies in Singapore. “Lots of people around the world think having secure communications at a quantum level is important. The Europeans, the Americans had the lead, but now the Chinese are showing the way forward.”

Quantum communications use subatomic particles to securely communicate between two points. A hacker trying to crack the message changes its form in a way that would alert the sender and cause the message to be altered or deleted.

Researchers around the world have successfully sent quantum messages by land. But a true satellite-based network would make it possible to send quickly encrypted messages in an instant around the world and open the door to other possible uses of the technology.

Cybersecurity has been a major focus in recent years for China, which has pushed regulations aimed at limiting technology imported from the U.S. in the wake of Edward Snowden’s revelations of widespread surveillance by the U.S. through the use of American hardware.

China has in turn been repeatedly accused by the U.S. of hacking into computer systems to steal commercial secrets and information that could harm American national security.China has rejected claims that it runs a state-sponsored hacking program and says that it is among the leading victims of cybercrime.

Quantum messaging could become a major defense against hackers and have applications ranging from military and government communications to online shopping.

The biggest challenge, Ling said, is being able to orient the satellite with pinpoint accuracy to a location on Earth where it can send and receive data without being affected by any disturbances in Earth’s atmosphere. The results of China’s tests will be closely watched by other research teams, he said.

  • Tesla: Removal of ‘Autopilot’ from Chinese site a mistake

Tesla said Monday that the term “Autopilot” was mistakenly removed from the electric car maker’s website for China, but it has been restored.

The company said it did revise some language on the site to make it clearer to drivers that Autopilot is a driver-assist system and not a self-driving system.

Tesla has been under pressure to stop using the term Autopilot in the U.S. following the death of an Ohio tech company owner in a Florida crash involving the system. Last week, a driver in Beijing relying on Autopilot mode sideswiped a car parked on the side of the road. Tesla says the driver’s hands weren’t detected on the steering wheel during the crash. The company says drivers using Autopilot must keep their hands on the wheel and be ready to take over.

Revisions to the language on websites have been under way for weeks to address “discrepancies across languages,” the Palo Alto, California, company said in a statement. The timing had nothing to do with current events or articles, and Tesla has no plans toremove any references to Autopilot from any website, spokeswoman Khobi Brooklyn said.

Tesla’s Autopilot system uses cameras, radar and computers to detect objects and automatically brake if the car is about to hit something. It also can steer the car to keep it centered in its lane. The company says that before Autopilot can be used, drivers must acknowledge that it’s an “assist feature.”

In July, Consumer Reports magazine said the company should drop the name because it gives car owners too much trust in their car’s ability to drive itself.

The influential magazine also said that Tesla should disconnect the automatic steering system until it’s updated to make sure a driver’s hands are on the wheel at all times.Tesla’s system currently warns drivers after a few minutes of their hands being off the wheel.

At the time, Tesla said data it collects show drivers who use Autopilot are safer than those who don’t.

  • Buffett’s company adds to stakes in Apple and Phillips 66

Warren Buffett’s company is taking an even bigger bite of Apple stock and adding to its already sizeable stake in Phillips 66.

Berkshire Hathaway Inc. filed an update with regulators Monday on its roughly $130 billion U.S. stock portfolio.

Berkshire said it held 15.2 million Apple Inc. shares at the end of June, up from the 9.8 million share stake it first disclosed in the spring.

The Apple investment raises eyebrows because Buffett has always been reluctant to invest in technology companies. It may have been the work of one of Berkshire’s two other investment managers.

The quarterly filings don’t disclose who is managing Berkshire’s Apple investments, and Berkshire officials don’t generally comment on the filings.

Buffett tends to handle the larger investments in Berkshire’s portfolio, such as IBM, Wells Fargo and Coca-Cola. He has said that investments of less than $1 billion are likely to be the work of Ted Weschler or Todd Combs, who each handle about $9 billion for Berkshire.

At the end of June, Berkshire held 78.8 million Phillips 66 shares, which represents about 15 percent of the oil refiner’s stock. That’s up from 75.6 million shares three months earlier.

Buffett’s company cut its Wal-Mart Stores Inc. stake to 40.2 million shares in June from 55.2 million in the spring.