Pokémon Go has emerged in just a few days as a cultural phenomenon.
In an even shorter amount of time, it's also looking like a savior for Nintendo.
The hope that Nintendo may have finally cracked mobile gaming sent shares in the company soaring, adding around $7 billion to the value of the company in the past couple days of trading in Japan.
The frenzy reflects just how unexpected of a success Pokémon Go has been, and how low expectations have been for the Japanese video game company.
Nintendo had previously eschewed mobile gaming, a stance that its former CEO Satoru Iwata has been walking back in recent years. Nintendo launched its first mobile game, Miitomo, in conjunction with DeNA in February.
Now, there's some thought that the success of Pokémon Go has shown that when Nintendo wants to do mobile, it can produce hits with its stable of popular characters.
Analysts are cautiously optimistic, noting that initial user statistics and the game's structure are conducive to getting people to spend money.
"As users build their Pokemon inventory, spending money becomes needed to store, train, hatch, and battle," wrote Macquarie Capital Securities analyst David Gibson.
The game quickly rose to become the top grossing game in the U.S., Australia and New Zealand — the only three regions in which it has been released so far. Its upcoming launch in the United Kingdom, Europe and Japan is expected to be similarly successful.
The main issue, as Gibson pointed out, is that Nintendo only gets a cut of the money.
Nintendo's interest here is slightly convoluted. Nintendo owns part of The Pokémon Company, with Japanese video game companies Game Freak and Creatures also owning pieces of Pokémon.
Nintendo also owns a piece of Niantic, thanks to a $20 million funding round that included Nintendo, Google and The Pokémon Company.
That means the cash from Pokémon Go is split between Apple's App Store, Niantic, The Pokémon Company and Nintendo.
There's also some doubt about whether Pokémon Go and any other mobile game can sustain the kind of momentum that would result in a meaningful difference for Nintendo.
"The recent share price rally accordingly looks excessive based on profits from Pokémon Go alone," Nomura analysts said in a note.
Just what Nintendo has in mind for mobile in the long term, however, isn't entirely clear. The company is readying its newest console, the secretive "NX," which could be a handheld piece of hardware similar to its 3DS.
Whether or not Pokémon Go ends up driving financial success for Nintendo, investors are clearly looking for reasons to believe in the company's mobile strategy. In March, Nintendo shares jumped 8% after Miitomo proved to be a small hit.
If Pokémon Go does end up being the start of something huge, not just as its own game but also for Nintendo's broader mobile strategy, investors that jumped in early could reap rewards.
And if Nintendo can replicate even some of Pokémon Go's success with titles from Zelda or Mario Bros., it would be in line for a far bigger payday.