Amazon.com Inc. AMZN -0.35% knows what hundreds of millions of people buy, and it already has millions of its smart speakers listening inside people’s homes. Now it is selling devices that can watch you, too.

The Seattle-based retailer on Tuesday unveiled the new Echo Show, a successor to its speakers powered by artificial intelligence and released in 2014. The Echo Show builds on its predecessor by adding a 7-inch touchscreen and a camera for video calling and other capabilities.

…

It is inevitable Amazon and others would add a visual component to smart speakers to better monetize them, said Albert Gidari, director for privacy at Stanford Law School’s Center for Internet and Society.

“The question is: What is the screen going to see, and who is going to see it?” Mr. Gidari said. Those are important questions, even with current privacy controls, he said.