Norman Foster-led Foster + Partners has completed its first Apple project - a retail Apple store - in Istanbul, Turkey. The store is the first of a series of retail spaces that the architectural firm will be building for the tech giant.

The store is located at the Zorlu shopping center in Istanbul and features a glass façade. It is a two-story, underground store that sits below the main plaza of the shopping center. There is an 18 square-meter void, which was initially planned as a descending water feature.

The store has an interesting layout, especially because it is underground. From outside, you can only see a frameless glass box rising from the ground. As you approach it, the glass box gives you a view of the store below.

Designboom is calling the store a "rectangular lantern that glows above the ground."

Inside the store, you can see the patented rectangular tables and glass walls with lighted ceilings.

Check out more photos here.

Foster + Partners' next store is slated to open in San Francisco and they have already submitted plans of the store.

The retailer transformed consumer-technology experience. Currently, Apple has about 254 stores in the United States and about 400 stores worldwide, reports Dezeen.

Apple had recently patented its distinctive "glass façade and rectangular tables." Late founder Steve Jobs once said:

"Unless we could find a way to get our message to customers at the store, we were screwed."

And now the retail spaces of Apple seem to be striving to do just that - pitch their products to customers in a completely consumer-friendly manner. According to a GSM Arena blog, Apple's "play-with-everything philosophy" has helped popularize the stores.

However, some experts think that Apple's retail growth isn't really moving ahead much.

"It's not evolving as fast as it could be. Since Steve [Jobs] passed away the momentum has slowed down a bit. It's imperative Apple shifts again. They should really refresh (their retail offering) every five years," said Tim Kobe, founder and CEO of design studio Eight Inc., who also developed the Apple Store Concept with its first CEO, to Dezeen.

When urged about why Apple wanted its own branded stores, Kobe said:

"...for Apple to step out, redefine itself and really express its brand values through that experience, (they had to open their own stores). And once that happened, the traditional third-party channels were beating a path to their door. But it was really about controlling the message and drawing on the customer experience."