Apple’s fleet of retail stores comprise an integral component to Apple’s marketing efforts, and more importantly, to its bottom line. During the June 2011 quarter, sales at Apple retail stores increased 36% from the same quarter a year-ago. When the dust cleared, retail sales came in at $3.5 billion. Meanwhile, foot traffic at Apple’s retail stores increased from 60.5 million in the June quarter of 2010 to 73.7 million people in the most recent quarter. Not too shabby given the doubt and pessimism that shrouded Apple’s retail initiative when it first got off the ground.

Now Apple doesn’t control the lion’s share of the smartphone market, but when it comes to smartphone profits, Apple controls an astounding 66% share. In a similar vein, Apple may not operate the most retail stores in the US or even make the most money from its retail ventures, but when it comes to sales per square foot, Apple is King.

According to a new study from RetailSails, Apple’s US-based retail stores earn more money per square foot of real estate than any other US-based retail chain in the country, besting premium brands like Tiffany & Co and Coach. Specifically, Apple’s sales per square foot check in at $5,626 which is almost twice as much as the $2,974 earned by Tiffany & Co.

The only other technology-oriented outlets that made the top 10 are GameStop and Best Buy which each generate $1,009 and $831 per square foot respectively.

As successful as Apple’s retail stores are, the company isn’t resting on its laurels and has been opening a bevy of new stores as of late. This weekend, for example, Apple plans to open up new stores in Charlotte and Little Rock, along with a new store in Paris. Earlier this month, Apple opened retail stores in Utah, California, Canada, and Australia.

via Retail Sales