AS THE coronavirus pandemic shuts down public life on the streets, a new kind of life is opening up online. Many people who are lucky enough to still have their jobs are working from home, often experimenting with video chats and virtual offices for the first time. Students are attending classes and visiting friends online, too. Covid-19 could change the internet as profoundly as it is changing our handwashing habits.

Our arsenal of must-have apps has already started to shift. Almost overnight, the videoconferencing app Zoom has gone from obscurity to necessity. People are using it to …