Booksellers are always looking for new ways to attract more customers to their stores, but it’s doubtful that many thought that Pokémon would be the answer. The sudden popularity of the smartphone video game Pokémon Go is driving people into bookstores and, in some cases, driving up sales.

The augmented reality app, based on the Pokémon gaming franchise, has become a viral phenomenon since it was released in the U.S. last week. The media has reported that the number of people playing the app may soon eclipse the number of people using Twitter.

Those playing Pokémon Go rely on a map informed by the GPS on their smartphones, which leads them on a hunt to catch new Pokémon, find unique items, and battle their prize Pokémon with other players. Locations in the real world are turned into hotspots in the game: your local church could be a Poké Gym, where users can battle their Pokémon against each other; a bookstore down the street could serve as a Poké Stop, where players can pick up important items; etc.

The nature of the game is proving a boon for foot traffic at some bookstores, like Wild Detectives Bookstore in Dallas, Tex.

"There is a Poké Gym across the street, so that really helps. It's crazy,” said Sam Villavert, a barista at the store. “People pop in, get their Pokémon, or whatever it is they are doing, [and maybe] they have a coffee." Villavert added that a lot of Pokémon Go players showing up at the store are first-time customers.

Book Garden, in Bountiful, Utah, is a Poké Stop, and Tonya Youngbird, a bookseller at the store, said she’s seen a spike in the number of families and groups stopping by the store. This has meant a spike in book sales. "We have lots of people coming in with their kids and getting their Pokéballs," she said. "Once they're in the store, they browse and realize we have a lot [of things] they didn't know we have."

Players of the game can also attract other players to a location by planting “lures,” in-game items that attract wild Pokémon, at official Poké Stops. John Beresford, manager of Pandemonium Books & Games in Cambridge, Mass., said his store has benefited from a lure, mentioning a “slight uptick” in sales.

Other booksellers, who acknowledge that their foot traffic is being affected by the game, are less certain about monetary benefits.

Peter Blackshear, of the Ann Arbor, Mich.-based Bookbound, said he's unsure whether the game has actually affected business. Noting that more people seem to be loitering outside the store, Blackshear said they "don't seem too serious about books."

Other booksellers, lacking the prestige of being official Poké Stops, are hoping to capitalize on the kind of loitering Blackshear described.

Emily Hall, owner of Main Street Books in Charles, Mo., who is a fan of the game, has put a sign in front of her store advertising her shop as "an unofficial Poké Stop." The store is offering 10% off on purchases made by customers who can show a bookseller a screenshot of a Pokémon they caught in the game.

"Some friends of mine are going to try to figure out if, or how, they can get Main Street Books to be a stop," Hall told PW. "I think everything is predetermined, but a girl can dream."

For all of the Pokémon Go mania, Pokémon books don't necessarily seem to be flying off shelves. "I haven't seen an increased demand,” Hall said. "But I ordered the first three volumes of the Pokémon Adventures manga series and a couple Pokémon guides this morning, so when they get here tomorrow I'm going to set up a display."