After Apple Inc CEO Steve Jobs' remarked that his company had sold more iPhones than Research in Motion (RIM) had sold BlackBerrys, RIM hit back yesterday saying customers were getting tired of "being told what to think by Apple."

Steve Jobs was on a conference call on Apple's quarterly earnings on Monday when he said, "We have now passed RIM, and I don't see them catching up with us in the foreseeable future."

"I think it is going to be a challenge for them to convince developers to create apps for yet a third platform after Apple and Android's App store."

The Apple CEO pointed out that Apple had sold 14.1 million iPhones last quarter compared to RIM's 12.1 million BlackBerrys, adding that it was going to be tough for RIM to create a competitive software platform and convince developers to make applications for it.

RIM Co-Chief Executive Jim Balsillie fired back in an emailed message, saying, "We think many customers are getting tired of being told what to think by Apple," the Wall Street Journal reported.

Jobs also criticised the seven-inch tablet computers 'PlayBook' manufactured by RIM.

"This size isn't sufficient to create great tablet apps in our opinion," Jobs said. The iPad has a 9.7-inch screen.

"The seven inch tablets are tweeners, too big to compete with a smart phone, and too small to compete with an iPad," Jobs had said.

To this Balsillie responded that "for those of us who live outside of Apple's distortion field, we know that 7-(inch) tablets will actually be a big portion of the market and we know that Adobe Flash support actually matters to customers who want a real web experience," he said.

"We also know that while Apple?s attempt to control the ecosystem and maintain a closed platform may be good for Apple, developers want more options and customers want to fully access the overwhelming majority of web sites that use Flash."

According to the Wall Street Journal, the high-level sniping underscores the brutally competitive nature of the smartphone market.

"RIM's position near the top is under assault by Apple, whose iPhone is making inroads in the corporate market and whose iPad has been in stores since April," the report said.

Apple itself is facing challenges by the fast-selling phones built on Google's Android software, which is competing for the attention of developers with Apple's iOS software for the iPhone and iPad.