Apple Inc. (Nasdaq: GOOG) says Google Inc.’s (Nasdaq: GOOG) YouTube won’t be included in the next version of the software used in the iPhone and iPad, the latest evidence of escalating competition between the two companies.

Apple has featured YouTube as a core application since the iPhone debuted in 2007. As Google has pushed into the smartphone market, the relationship between the two companies has frayed. Google’s Android software is now the world’s largest operating system for smartphones, used by Apple’s rivals including Samsung Electronics Co.

Apple also plans to replace Google’s maps application in the next iOS release with its own.

Users will see the effects when the next version of Apple’s mobile software, called iOS 6, is released later this year. A license expired that allowed the company to include YouTube, said Trudy Muller, a spokeswoman for Cupertino, California-based Apple. As a result, the YouTube app won’t come pre-installed on future iPhone, iPad and iPod Touch releases or if a user downloads iOS 6 to existing devices.

“Customers can use YouTube in the Safari browser, and Google is working on a new YouTube app to be on the App Store,” Muller said.

Apple is scheduled to unveil the next iPhone – which is expected to feature the latest iOS version – at an event on Sept. 12, two people familiar with the plans said last month.