UPDATE: Embedded above and online here: a video I recorded with WSJ Live about the story.

The story begins:

Global technology firms are pitching in on earthquake rescue efforts in Nepal with services such as free calls to and from the country to functions that track survivors and relay the news to worried relatives and friends overseas.

Search giant Google Inc. on Saturday launched its Person Finder service, which allows users to post and search for information about missing friends and loved ones. The feature, which Google created in response to the destructive 2010 earthquake in Haiti, showed it was tracking 5,100 records as of early Monday afternoon Asia time.

Facebook Inc. activated Safety Check, which allows users in areas affected by the earthquake to select a notification alerting friends on the social network that they are OK.

“When disasters happen, people need to know their loved ones are safe,” Facebook Chief Executive Mark Zuckerberg wrote Saturday in a post on his Facebook page, referring to the feature developed last year. “It’s moments like this that being able to connect really matters.” The post was shared more than 41,000 times and received more than 263,000 likes.