Nintendos share price soars but there have been safety fears over players visiting secluded locations late at night
An app that began as an April Fools joke has become a worldwide phenomenon, taking gamers out of the living room and on to the streets as they compete to capture, train and battle Pokmon characters using their mobile phones.
In just seven days since the game was released in the US, Australia and New Zealand, Pokmon Go has now almost certainly exceeded Twitters 65 million American users, and the games servers have repeatedly crashed under the strain of its popularity.
The share price of Nintendo, which owns a third of the Pokmon Company and an undisclosed stake in the games developers Niantic, has rocketed by 50%, and the release of the game in other countries including the UK has been put on hold while the developers struggle to cope with demand.
Pokmon Go is a spin-off of the long-running Pokmon series, in which players capture and battle the titular creatures (short for pocket monsters) in their quest to become the greatest Pokmon trainer in the world. Unlike in earlier videogames, players move around the real world looking for Pokmon to capture.
When the app is opened, it shows a map of the area around the player, with various points of interest marked statues, clock towers and so on. Physically walk up to one of the points, referred to in the game as a Pokstop, then tap an icon on screen and youre rewarded with items and experience points.
But the core of the game is the Pokmon themselves, which can appear anywhere, any time (though often themed around the location, with ghost-type Pokmon appearing in graveyards and water-type creatures near lakes and rivers). Tap on one of them and a minigame starts, in which the aim is to catch a Pokmon.
The game is not just for solo players. Some locations have become hubs of Pokmon activity. New Yorks Central Park, for instance, has been bustling not just with the usual crowds of sightseers but with players checking their phones for nearby Pokmon.
The real-world aspects of the game have also, inevitably, led to a darker side emerging. Police in Missouri reported that a group of men were waiting near a Pokstop in a secluded location to target players, and a woman from Wyoming stumbled upon a dead body while trying to reach a water-type Pokemon apparently living in a river by her trailer.
In New Jersey, police were moved to remind residents: Normally you wouldnt go to a deserted alley at 3am. That shouldnt change just because an app said you should.
The craze around the game is a huge step up from its humble beginnings as an April Fools joke launched by Google in 2014. For one day, Pokmon appeared on Google Maps, letting browsers search for them at real-world landmarks. People seemed to really love that combination of Maps and Pokmon, said Niantic Labs chief executive, John Hanke.
But even Hanke couldnt have predicted the success of Pokmon Go. Data from the analytics firm SimilarWeb suggests that 3% of all Americans opened the Pokmon Go app last Friday, just slightly below the 3.5% who opened Twitter, and the game has already been installed on more American Android phones than the dating app Tinder.
For those in Britain wanting to see what the fuss is about, the best bet is simply to sit tight and wait for the official launch originally planned to be a few days after the US one, but now delayed because of the unexpected capacity issues.
Tech-savvy players have been able to circumvent the region restrictions, but security companies have warned that users attempting to break region locking may end up accidentally infecting their phones with malware.
For Niantic and the Pokmon Company, the question is whether they can maintain the immense momentum that Pokmon Go has built up. Some mobile games, such as Candy Crush and Clash of Clans, have used a viral start to build a viable long-term business, but others, including Flappy Bird and Draw Something, have been flash-in-the-plan sensations.
The Pokmon Company has spent 20 years telling players to catch em all. Now it has to follow its own advice.