On a recent evening in the West Village of Manhattan, Dorothy Wiggins, a petite 98-year-old woman wearing a dark coat and a pink scarf, left her townhouse to check out Little Ruby’s Cafe, a chic new restaurant in her neighborhood. Inside, she approached the hostess.

“I remember this place when it was the other place, the Riviera,” Mrs. Wiggins said. “It was so tacky next to this. You really jazzed up the space.”

“It’s an Australian restaurant,” the hostess said.

“Australian?” Mrs. Wiggins replied.

As she processed this information, the hostess asked if she had a reservation.

“I just live in the neighborhood, and my husband painted this place once,” Mrs. Wiggins said. “I was just curious.”

She took her leave and walked back to her brownstone. She wasn’t alone. Trailing her was Michael Astor, a freelance journalist who was discreetly filming her outing with a pocket-size gimbal camera.

The scene he had just recorded would soon be posted to the TikTok and Instagram accounts he manages, both called @dorothylovesnewyork, which have made Mrs. Wiggins an unlikely social media celebrity.

Tens of thousands of people follow the accounts, which chronicle Mrs. Wiggins’s late 90s as she navigates life in New York and the Hamptons equipped with a wooden walking staff, vintage hats and a bone-dry sense of humor.

In one video, she becomes frustrated when a server at a Midtown jazz club can’t get her drink order quite right (a shot of Dewar’s in an ice-filled highball, with a water back). In another, she complains about “awful Montauk oysters” to the operator of an East Hampton seafood shack. The most popular clip, with more than nine million views on Instagram, shows her hitting a serve on a tennis court in Amagansett.

“Chrissie Evert commented on my serve,” Mrs. Wiggins said in the living room of her brownstone, where she and Mr. Astor, 59, were seated next to a crackling fire. “She said it looks like her serve.”

Part of the accounts’ charm lies in her indifference to social media.

“I’m a funny one to become popular, because I scorn it all,” she said. “I hate walking down streets and seeing people clutch their phones like they’re clutching their heart.”

“TikTok feels stupid to me,” she continued. “You need more than a momentary thing. I watched ‘Casablanca’ the other night. Now that’s the perfect length for a movie. I just think it’s bad for concentration and that it’s going to make people stupider. My husband could recite A.E. Housman’s poetry by heart.”

Guy Wiggins, a painter and former Foreign Service diplomat, died three years ago, at 100. Mrs. Wiggins, who was raised in the Forest Hills neighborhood of Queens, met him when she was in her early 30s, and they were married for 61 years.

“When my husband died, I was totally devastated,” Mrs. Wiggins said. “My whole life was him.” Referring to her social media accounts, she added, “My son started this, because he thought it would take my mind off the grief.”

Mr. Astor, a family friend and a former reporter for The Associated Press, was commissioned by one of the couple’s sons in 2019 to make a short documentary about his aging parents. After it was completed, and Mr. Wiggins had died, Mr. Astor kept filming. A year ago, he started posting clips on social media. The account received its first spot of publicity over the summer, in The East Hampton Star.

“We never expected Dorothy to become Insta famous,” Mr. Astor said. “What people are seeing on the TikTok and Instagram are all collages I’ll eventually make sense of in a proper film.”

Mr. Astor documents Mrs. Wiggins several times a week and edits footage in the library study on the townhouse’s second floor. He keeps her informed of their most viewed clips and the reactions from commenters. (Mrs. Wiggins has an iPhone but does not use TikTok or Instagram.)

“We’re always at loggerheads,” Mr. Astor said. “Everything after the 1960s is a disappointment to her. I think TikTok is a medium that’s allowed me to pull people into something deeper about her life.”

“It’s also about someone dealing with growing older,” he added. “Especially an older woman — a person who often disappears in our society.”

Mrs. Wiggins got up from her seat and fetched a self-published book, “Wiggins in Love,” which is filled with photographs of herself and her husband, along with scans of birthday and Valentine’s Day letters he had written to her over the years. Turning the pages, she came across a sketch of his that depicted them seated on a couch with drinks.

“Our evening cocktail hour was sacred,” Mrs. Wiggins said. “No matter what, we never missed our cocktail hour.”

On a Friday evening, Mr. Astor was filming Mrs. Wiggins as she entered the Salmagundi Club in Greenwich Village, where she and her husband were regulars. She walked down the creaky stairs to the Wiggins Bar, which was named after her husband’s family; his father was the cityscape painter Guy Carleton Wiggins and his grandfather was the landscape artist John Carleton Wiggins. One wall is decorated with paint-splotched palettes and photographs of the Wiggins men.

“The usual, Mrs. Wiggins?” the bartender asked.

She sat with her Dewar’s while Mr. Astor scrolled through his phone, checking out comments on their latest post. He relayed a roll call of updates: The comedian Ellen Cleghorne had just followed them, and someone wanted to ship her some oysters from Maine. He also mentioned that they needed to start planning an event at which a few of her fans could join her for a drink at the Wiggins Bar.

“Dorothy and alcohol does really well,” Mr. Astor said. “Her followers like the idea that someone is 98 and still drinking.”

But Mrs. Wiggins seemed more interested in gazing at a hanging still life of oysters painted by her husband than in discussing social media engagement.

“As I said, I brush off the fame,” she said. “I love my fans, but I don’t put much stock in it, and think the whole thing is kind of silly.”

Then she grew reflective.

“Well, there was one comment I was touched by,” Mrs. Wiggins said. “Someone commented once they felt life was over for them. That they were depressed. But that after seeing my videos, they were inspired to keep going.”

“Now that I can understand,” she continued. “If I can show someone they shouldn’t give up on life, then I do care about that.”