Apple Stores drive so much traffic to shopping malls, Apple is able to negotiate cheaper rent. Apple Stores have been shown to increase sales in mall 10%, according to the Wall Street Journal.
Source: Wall Street Journal
The Nanjing East store in Shanghai is Apple's busiest. It gets 25,000 visitors per day.
Source: Apple
Apple leases about 4.9 million square feet of space for its retail operations.
Source: Apple 10-K filing
There were 437 Apple Stores at the end of 2014. 259 of them were in the US. The rest were international stores.
Source: Apple 10-K filing
Apple plans to open about 25 new Apple Stores in 2015. Most of those will be outside the US.
Source: Apple 10-K filing