In Mexico, politicians were cut off from their constituents. In Turkey and Kenya, shopkeepers couldn’t sell their wares. And in Colombia, a nonprofit organization that uses WhatsApp to connect victims of gender-based violence to lifesaving services found its work impaired.
In parts of the developing world, the cost of the Facebook outage was particularly acute. In India, Latin America and Africa, its services are essentially the internet for many people — almost a public utility, usually cheaper than a phone call and depended upon for much of the communication and commerce of daily life.
Cosas de Mujeres, the nonprofit in Colombia, has hundreds of interactions every month with Colombian women and Venezuelan migrant women who face domestic and emotional violence or are at risk of trafficking or sexual exploitation, said Ms. Berryhill, the organization’s director of digital operations.
“Usually we have phone operators receiving messages from women all day via WhatsApp, but that was not possible, and women could not contact us,” she said.
María Elena Divas, a 51-year-old Venezuelan migrant in Bogotá, Colombia, uses WhatsApp to take orders for snacks like empanadas.
“I didn’t sell anything today,” Ms. Divas said.
Across Africa, Facebook’s apps are so popular that for many, they are the internet. WhatsApp, the continent’s most popular messaging app, is a one-stop shop to communicate with family, friends, colleagues, fellow worshipers and neighbors.
In Kenya’s capital, Nairobi, anything from shoes and jewelry to plants and household appliances can be ordered for delivery from Facebook, Instagram and WhatsApp. In Johannesburg, vendors were cut off from Facebook Marketplace, which is used to sell everything from used cars to wigs and even corrugated iron shacks, known colloquially as zozos.
The use of WhatsApp has grown so much that at one point it accounted for nearly half of all internet traffic in Zimbabwe. During the outage on Monday, the chief government spokesman in Tanzania used Twitter to urge the public to “remain calm.”
“Our business came to a standstill,” said Lydia Mutune, owner of a pots and plants store in Nairobi that sells exclusively on Facebook and Instagram. “It was a wake-up call. It just showed me how my business and our lives are totally dependent on social media platforms.”
Drogasmil, a pharmacy chain in Brazil, takes many prescription orders via WhatsApp, said Rafael Silva, a Drogasmil pharmacist in Rio de Janeiro.
Selen Bayrak, owner of a small shop in Istanbul that sells spicy marmalades and sauces, said 80 percent of her sales were normally made through Instagram. She estimated that she managed to sell only a quarter of what she could have sold yesterday had Instagram not been down.
In Mexico, many small-town newspapers cannot afford print editions, so they publish on Facebook instead. That has left local governments without a physical outlet to issue important announcements, so they, too, have taken to Facebook, said Adrián Pascoe, a political consultant.
A municipality Mr. Pascoe is consulting for was unable to introduce its new services on Monday because the site was down. The announcement will take place on Wednesday instead, he said.
León David Pérez’s two companies, including Polimatía, which provides e-learning courses, rely on Facebook and Instagram to market their products. The customer service department is run on WhatsApp.