Pokemon Go: The eccentric genius behind the game
In his former office at Google John Hanke kept the shelves well stocked with games.
Computer games, obviously befitting a man obsessed with technology, but proper old-fashioned board games too.
Prominent among them were Risk, Settlers of Catan and Stratego. All three have the same simple aim: to take over the world.
Today the 49-year-old floppy-haired Hanke can lean back in his new office chair a few blocks down along the city's Embarcadero and put his feet up.
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With the help of a small group of visionaries that includes a Japanese computer game wizard and a British advertising guru, Hanke's digital start-up Niantic has given the world the phenomenon that is Pokemon Go.
Global domination is complete.
The spark of genius behind this success story is to be found in Japan, where the famously reclusive computer developer Satoshi Tajiri invented Pokemon back in 1990.
Originally launched on the Nintendo Game Boy, Pokemon became a huge gaming, television and film franchise - even before this latest incarnation it had notched up 200 million sales, making it one of the biggest-gaming series of all time.
In one of his rare interviews, given in 1999, Tajiri said he came up with the idea after obsessively catching insects when he was a child growing up in the western Tokyo suburb of Machida: "I think a lot about kids and what they need and want to make their lives better."
Now aged 50 and worth an estimated US$5.1 billion, Tajiri continues to work on Pokemon in Japan and retains his boyish looks despite a punishing schedule of 24 hours work and 12 hours sleep. He has never been drawn on why he keeps such a low profile.
John Hanke enjoys a more public persona in Silicon Valley, though he too values his privacy. He is married with three young children but keeps his family well out of the limelight.
Those who know him speak of the man who hails from Texas as a true innovator.
Perhaps, even, the next digital entrepreneur to follow in the footsteps of Apple founder Steve Jobs. "John Hanke is an absolute genius," says David Jones, the only British investor with a stake in Niantic.
Last November, Jones joined a few other select Silicon Valley investors who backed the company as part of its first funding round. While he won't say how much he has invested or how much he stands to gain, he adds: "It's pretty fair to say, anybody who invested would have done well."
Jones says he was attracted to invest by Pokemon Go's fusion of the real and digital world - and its potential for businesses.
"The opportunity for brands is enormous," he enthuses, "but both Niantic and Pokemon are going to be incredibly discerning and selective about what brands are allowed to do in the game."
For Jones, Hanke "is a visionary in that he understands not just where the future is going but creates the things that will change that future. We're all talking about Pokemon Go but in reality a whole new world has just been created."
Pokemon Go is not the first time Hanke has reinvented our reality.
At the turn of the millennium, the former United States government worker founded the digital mapping firm Keyhole, which was bought by Google and turned into the game-changing Google Maps, released in 2005.
Hanke remained at Google for another decade, initially launching Niantic within its fold before setting up as an independent company in October 2015 with $30 million investment from the Pokemon Company, Google and Nintendo.
"He's one of those really smart guys who can be quite hard to speak to," says Steve Peters, a 55-year-old designer who worked with Hanke at Niantic prior to the split from Google.
"A lot of Mensa-level geniuses at Google are like that. He's eccentric, in a good way.
"He's stuck by that vision that the world is a great place to be present in, not behind a computer screen. It's a very noble cause."
- The Telegraph, London