Unless you’ve been living under a rock this past week, it’s impossible not to have heard about the Pokémon Go craze. A mobile game released for smartphones on July 6, the game has more users than Tinder and is on the verge of surpassing Twitter in app downloads.

In less than a week, Pokémon Go boasts over 20 million daily users of all ages, making it the most popular mobile game in American history. It’s not unusual to see throngs of people gathered around a particular place or pulled over in their cars, trying to catch Pokémon.

While all of this translates into big money for Nintendo, whose stock rose 23 percent this past Monday, it’s a big headache for public spaces attracting Pokémon Go players.

The Nintendo game revolves around three key tenets:

  1. Your character, or avatar, follows you across a map of the real world, aided by your smartphone’s navigation system.
  1. A Pokémon character randomly appears on that map. Through the use of map technology paired with augmented reality, a user hunts these digital Pokémon that appear in the player’s camera frame when encountered. Think of it as a digital world superimposed on the real world.
  1. In the world of Pokémon Go, real-life landmarks can become “Gyms,” where Pokémon can fight one another, or serve as “Poké Stops” where a player picks up items.

But here’s where the controversy comes in: These Pokémon Gyms and Poké Stops are mapped out in places like the United States Holocaust Memorial Museum, the State Auschwitz-Birkenau Museum, the 9/11 Memorial and Arlington National Cemetery. In these sacred spaces, digital worlds collide with real-life actions. It can turn into a disconcerting situation that is not easily rectified since the game randomly generates a Pokémon based on a player’s current location. In other words, players, rather than owners of the physical location, determine where the game is played.

In an email exchange with JewishBoston, Andrew Hollinger, the Holocaust Museum’s director of communications, said, “Playing Pokémon Go in a memorial dedicated to the victims of Nazism is extremely inappropriate.” The Jewish Telegraphic Agency reported that the Auschwitz-Birkenau Museum tweeted that it will ban the new smartphone game on its premises because it is “disrespectful on many levels.”

To complicate matters for the Holocaust Museum, The Washington Post reported that a Pokémon called Koffing, which emits poisonous gas, was floating near a sign for the museum’s Helena Rubinstein Auditorium. The seemingly random sighting, which might be a hoax, was particularly disturbing since the auditorium often screens testimonials of Jews who survived the gas chambers.

Whether it’s a hoax or not, the museum was concerned about the Koffing image, as well as similar potential incidents. Hollinger noted, “We are attempting to have the museum removed from the game.” He further explained that while “the museum encourages visitors to use their phones to share and engage with museum content while [visiting], this game falls far outside of our educational and memorial mission.”

Niantic Labs, which partnered with Nintendo to create Pokémon Go, could not be reached for comment.