After much cry, hugs, blame games, it seems Steve is coming heavily on those who had put him on defensive mode after launch of company’s flagship product iPhone 4.0. A Sr. Executive, in-charge of iPhone, has recently departed from company after a series of stumbles with the new device as sources confirmed on Saturday.

Mark Papermaster, Apple’s Sr. Vice President of mobile device, has left the company on Saturday, an Apple spokesperson informed to WSJ with no further details. Mr. Papermaster, joined Apple from International Business Machine (IBM), has been in the company for just 15 months. After series of stumbles Apple faced for iPhone 4.0, Mr. Papermaster was a falling out with Steve Jobs CEO, Apple Inc, said by few sources.

Exactly how much the problems with the iPhone 4 played in Mr. Papermaster’s exit is unclear. The iPhone 4, a key device for Apple, has been beset by issues such as antenna reception and delayed production of a white version of the gadget. Several people familiar with Mr. Papermaster’s situation said his departure was driven by a broader cultural incompatibility.

Mr. Papermaster lost his confidence with CEO Steve jobs and was kept apart from crucial management meetings from last couple of weeks, sources said. Furthermore sources said that Mr. Papermaster was not able to in-line with company’s creative thinking ideology, where every manager keeps some crucial initiaves with himself instead of delegating to his team. Sources said Mr. Papermaster had difficulties maneuvering Apple’s internal politics.

“This guy came from IBM and he was in charge of iPhone 4 hardware, but IBM doesn’t have antenna technology,” said Brian Marshall, an analyst with Gleacher & Co. Added Gene Munster, an analyst with Piper Jaffray & Co., “It’s too coincidental not to be related to the antenna issues.”

The iPhone 4, released in late June, is a hit device that has spawned an uncharacteristic number of stumbles for Apple. Initial offer of $199, handset attracted multiple of embarrassments to Steve Jobs, CEO Apple Inc, for releasing bugged device ( Antennagate issue ) and due to delay in lunch of White iPhone 4.0 handset. Steve tried to encounter handset Signal strength issue by failed attempt of showing similar issues with other phones which had been criticized by other handset manufacturer like Nokia & Samsung.

iPhones are the largest part of Apple’s business, comprising 34% of overall revenue. In its most recently reported quarter, Apple said iPhone revenue totaled $5.3 billion. Recently Apple had announced its last quarter financial result which crossed $16 billion mark due to huge success of iPad and iPhone 4.0.

Mr. Papermaster’s departure shows how difficult it can be for an outsider to succeed at Apple. While some of the company’s top executives who came from other corporations have thrived—notably Chief Operating Officer Tim Cook, who was previously at Compaq Computer Corp., and retail chief Ron Johnson, who joined from Target Corp.—others haven’t fared as well. For instance, Apple has gone through general counsels that it hired from IBM and Oracle Corp. since 2006.

Mr. Papermaster’s recruitment to Apple in late 2008 was controversial. His former employer, IBM, filed a lawsuit against the executive for violating a noncompete agreement. Mr. Papermaster didn’t start at Apple until April 2009 after the dispute was resolved. He succeeded Tony Fadell, a longtime Apple executive who had a key role in launching the iPod business, which helped fuel the company’s growth.

A spokesman for Apple said Mr. Papermaster’s duties will be handled by Bob Mansfield, the company’s senior vice president of computer engineering. The spokesman said Mr. Mansfield, who was featured in the iPhone 4 promotional video released in early June, already manages some aspects of Apple’s mobile-device technologies, such as the device’s “Retina” display and A4 processing chip.