Scott Forstall at iPhone 5 launch (Credit: Joanna Stern / ABC News)

Monday Apple announced that Scott Forstall, its head of software for the iPad and iPhone, would be leaving the company at the end of the year. It was a dramatic change for the Cupertino, Calif., company, and many analysts surmised that the ousting was a result of the problems associated with Apple's iOS Maps and Siri applications.

The Wall Street Journal, however, is now reporting that Forstall was asked to resign after he refused to sign the Maps apology letter issued by Apple CEO Tim Cook in September. Following widespread criticism about the new Maps app, which replaced Google maps in iOS 6, Tim Cook apologized to the public on Apple's website and suggested other maps apps visitors could use while Apple fixed the problems.

"The incident was the latest clash between Mr. Forstall, who oversaw Apple's mobile software unit, and other executives at the company. It led to one of the most significant management shake-ups in Apple's recent history, and its most sweeping changes under Chief Executive Tim Cook," the Wall Street Journal wrote.

This isn't the first time we have heard of Forstall's problems with other exeutives at the company. A story in the October issue of Bloomberg Businessweek described Forstall as "polarizing" and difficult to work with. The Wall Street Journal similarly said that Forstall wasn't always "cooperative" and seemed to brag about his relationship with Steve Jobs within the company.

"Without Mr. Jobs to mediate, tensions between Mr. Forstall and other executives built, according to the people familiar with the matter," the Wall Street Journal reported.

In Forstall's absence, Jony Ive, the head of hardware design, will step in and oversee what Apple calls "human interface."

"Of course, I've been not entirely politic in suggesting that the software design decisions (leather!) were not ones he approved of. So who decides about product design in a post-Jobs Apple? Seems like Ive is the answer," Jason Snell, editorial director for Macworld, told ABC News.

Apple also announced Monday that its head of retail, John Browett, would also be leaving the company. Apple's iPad Mini, which was launched last week, goes on sale Friday morning.