Constructive criticism: the week in architecture

While everyone was salivating over the launch of Apple's iCloud last week, Steve Jobs's other product launch garnered less attention. This was Apple's colossal new headquarters building in Cupertino, California – a gigantic white UFO sitting in 150 acres of landscaped parkland, designed for 12,000 workers. For obvious reasons, it has already been dubbed the "mothership". Nor has its designer been widely publicised, but we can reveal it's good old Norman Foster – who else?

Foster's people wouldn't reveal any details, but there are some in this video of Jobs presenting the scheme to Cupertino City Council, where it was received just as rapturously as a new iPad. "We do have a shot at building the best office building in the world," Jobs tells the awestruck councillors. "I really do think architecture students will come here to see this."

So what about the design? Foster has obviously taken a leaf out of Apple's chief designer Jonathan Ive's book – sorry, iPad. It looks like the circular trackpad of a giant iPod. If you run around the building very quickly, does a giant playlist light up in the sky? Mind you, by the time it's finished in 2015, it could look out of date.

The purity of the four-storey doughnut's impact on the landscape is also slightly compromised, it emerges, by other buildings on the site, including a four-storey car park. But none of the councillors seem to raise any objections; they're too busy geeking out their celebrity guest. "The word spectacular would be an understatement," grovels one of them, Mr Smithers-style. Just to drive the point home, Jobs mentions that Apple is the largest taxpayer in Cupertino, and hints that if he doesn't get his way, Apple will take their business elsewhere. Presumably the whole building will be able to take off and land in New Mexico, or something.

More good news for Foster and other British architects at this year's spurious but intriguing Best Tall Building awards. Foster's 80-storey Dubai tower, known as The Index – an energy-efficient, Italian futurist-looking affair – won in the Middle East and Africa category. Wilkinson Eyre won the Asia award for their colossal but elegant Guangzhou International Finance Centre – all 103 storeys of it. And Anglo-German architects Sauerbruch Hutton won the Europe award for their tasteful, low-energy Frankfurt office building, KfW Westarkade. The other winner was Frank Gehry's stunning Eight Spruce Street, a shimmering, steel-clad skyscraper that looks better than anything we're likely to find on the nearby World Trade Centre site. Though it does go by the pretentious name New York by Gehry, which makes it sound uncomfortably like a perfume.

Richard Rogers probably wishes he'd had Apple-style planning meetings over the Chelsea Barracks redevelopment in London. Instead, his design was controversially rejected when Prince Charles threw a royal spanner in the works last year, complaining about that vulgar hi-techie stuff to the Qatari royals.

No surprise that the revised design for the £3bn scheme is expected to be approved by Westminster council today, although the Qatari developers are said to be trying to reduce the amount of affordable housing in the scheme. No surprise, either, that the new plan, by Squire and Partners, Dixon Jones and landscape architect Kim Wilkie, is considerably more "traditional", laid out around London squares. Whoever designs the actual buildings will have to adhere to a preordained design code, which insists they "work in sympathy with surrounding character areas and architectural types without resorting to pastiche". Apparently Prince Charles is pleased.

After all this high-flying power architecture, we finally come right down to earth – to a little spot underneath a motorway flyover in east London. Here, a delightful temporary structure is under construction called Folly for a Flyover, as part of this year's Create festival. As designers Assemble explain, it's almost a stage set of a building, with curtain walls of wooden "bricks" made from salvaged timber, hung from scaffolding and held in place by cords running through the bricks. The pitched roof of the folly will poke out between the two roadways, and next to it are steps that serve as an outdoor seating area.

Not only is the folly ingenious and low-impact, it poetically turns a patch of dead urban space into a living venue. As the romantic engraving suggests, it's intended to feel like a forgotten piece of architecture which existed long before they built the A12 over the top of it – a building with a fictional history. Assemble, a collective of young designers and artists, were also behind last year's Cineroleum, a temporary cinema in a disused petrol station in Clerkenwell. This serves a similar function: it'll be a bar/cafe during the day, and in the evening you'll be able to watch films and performances on city themes, while traffic rumbles overhead, the Olympic building site bustles nearby and barges chug past on the canal. Sounds like the quintessential London summer experience.