Several developers of applications for iOS have observed that Apple engineers are testing the applications, so the company is checking if this version of the operating system functions well with titles from the App Store.
The same thing happened last year when Apple started to test iOS 5 in the same period and introduced it at WWDC 2011.
Some analysts believe that new features of the iOS 6 could be tested on the same day it is launched at the WWDC.
A recent report stated that Apple will drop the Google Maps program in favor of its own mapping software.
The new Maps app is expected to be a leading feature of the iOS 6.