He was innovative on store front

When the architect Peter Bohlin arrived for his first meeting with Steve Jobs, he wore a tie. "Steve laughed, and I never wore a tie again," Bohlin recalled.

Thus began a collaboration that has extended from Pixar's headquarters, completed in 2001, to more than 30 Apple Stores (and counting) around the globe, all designed by Bohlin and a team of architects from Bohlin Cywinski Jackson led by Karl Backus - and Jobs himself.

"The best clients, to my mind, don't say that whatever you do is fine," Bohlin said last week, a few days after Jobs' death. "They're intertwined in the process. When I look back, it's hard to remember who had what thought when. That's the best, most satisfying work, whether a large building or a house."

Just as Jobs transformed the notion of the personal computer and the cellphone, he left an indelible stamp on architecture, especially the retail kind, traditionally a backwater of the profession.

"No one in commercial architecture has ever channelled a product into architecture for a client the way Peter did for Apple," said James Timberlake, a founding partner of Kieran-Timberlake, who is now designing the new American embassy in London.

"Most commercial architecture is under-detailed, under-edited and underbudgeted. It's gross and ugly, and most of it is an eyesore on the American landscape."

The work of Bohlin and his colleagues for Apple, by contrast, is sleek, transparent, inviting, technologically advanced - and expensive.

In many ways, the retail architecture is simply the largest box in which an Apple product is wrapped, and Jobs was famously attentive to every detail in an Apple product's presentation and customer experience.

The extensive use of glass in structures like Apple's cube on Fifth Avenue in New York, its cylinder in the Pudong district of Shanghai or its soaring market hall on the Upper West Side of Manhattan have become so distinctive that Apple is seeking to patent the glass elements.

Bohlin's firm has won 42 awards for its work for Apple, and Bohlin himself was awarded the American Institute of Architects' gold medal in 2010.

In their years working together, Jobs and Bohlin, who is 74, appeared to have achieved a rare chemistry. Jobs was "a very public person," Timberlake observed. "That's in contrast to Peter. He's not a Frank Lloyd Wright or a Philip Johnson.

He doesn't sweep into a room and take over. You go to a design meeting, and it's more like a fireside chat." Backus, who lives in California and focuses full time on Apple work, said the team learned early on to approach Jobs with alternatives. "He liked to be presented with options and would often make very insightful suggestions," Backus recalled. "We all enjoyed the collaboration."

The notion of glass as Apple's signature architectural statement first appeared in the staircase in the company's New York store in So-Ho, housed in a historic building."We had a two-story space, which is a great challenge to get people to go up or down," Bohlin said.

"So we thought of glass. Steve loved the glass stair way idea. He got it. You make magic. We made these stairs that were quite ethereal." Just as Jobs obsessed over Apple products, he pushed Bohlin to make the glass structures ever more refined and pure."We got James O'Callaghan involved.

He's brilliant, a British structural engineer with offices in New York and London," Bohlin said. "Now we're cantilevering the stairs from top to bottom." In the newest Apple store, in Hamburg, Germany, the stairs float in space, attached only at the top and bottom. The fittings are embedded in the glass, "so you get this magical sleek profile when you look up the wall." Bohlin said.

"This is the kind of detail Steve wanted," he added. "We've been driving for this, doing more and more with less and less. This has been a vision of architecture since earlier in the last century.

Modernism, some people would argue, is doing more with less. Steve wanted us to push the edge of technology, but it had to be comfortable for people. Sometimes that idea got lost in modernism. It's an interesting challenge, how to marry the two."