Apple on Monday posted a 70% surge in quarterly earnings, eclipsing the profit reported by IBM. The maker of iPhones, the iPad and Mac computers reported a profit of $4.31bn in the September quarter, while IBM had earnings in the same period of $3.59bn, up 12% from a year ago.

Apple's revenue jumped 67% to $20.3bn from $12.2bn but the company’s shares fell in after-market trading after rising 10%  in the past week. Gross margin was 36.9% compared to 41.8% in the year-ago quarter. International sales accounted for 57% of the quarter’s revenue.

The biggest star of Apple's performance was the sale of 14.1m iPhones, 91% more than in the year-ago quarter.

Sales of the iPad failed to meet expectations.

Apple sold 3.89m Macs during the quarter, a 27% unit increase over the year-ago quarter. The company sold 14.1m iPhones in the quarter, representing 91% unit growth over the year-ago quarter. Apple sold 9.05m iPods during the quarter, representing an 11% unit decline from the year-ago quarter. The company also sold 4.19m iPads during the quarter.

“We are blown away to report over $20bn in revenue and over $4bn in after-tax earnings - - both all-time records for Apple,” said Steve Jobs, Apple’s CEO. “iPhone sales of 14.1m were up 91% year-over-year, handily beating the 12.1m phones RIM sold in their most recent quarter. We still have a few surprises left for the remainder of this calendar year.”

“We’re thrilled with the performance and strength of our business, generating almost $5.7bn in cash flow from operations during the quarter,” said Peter Oppenheimer, Apple’s CFO. “Looking ahead to the first fiscal quarter of 2011, we expect revenue of about $23bn and we expect diluted earnings per share of about $4.80.”

Jobs said in regard to Google’s portrayal of its Android smartphone software system as “open” and Apple’s as “closed” was a “smokescreen,” and that the real difference was that Apple’s combination of hardware, software and third-party commerce was integrated and more effective.

Jobs didn't comment on his company's profit but said: "I don't usually participate in Apple's earnings calls… but I just couldn't help dropping by for our first $20bn [revenue] quarter."

Results detail

In the third quarter IBM's revenues were $24.3bn, up 3% from a year earlier.

"In the third quarter we grew revenue in our hardware, software and services businesses, expanded margins and again increased earnings per share at double digits," said Samuel J. Palmisano, IBM chairman, president and chief executive officer. "We achieved excellent performance in our growth markets unit, reflecting sustained investments through the downturn and the continued strength of the infrastructure build-out in these countries.

"Looking ahead, we are uniquely positioned in the enterprise, investing in high value segments like business analytics, advanced systems and smarter planet solutions. As a result, we are confident we can deliver strong business performance to grow profit, return value to our shareholders and to achieve full-year 2010 diluted earnings per share of at least $11.40."

From a geographic perspective, the Americas’ third-quarter revenues were $10.2bn, an increase of 3% (2%, adjusting for currency) from the 2009 period. Revenues from Europe/Middle East/Africa were $7.4bn, down 6% (up 1%, adjusting for currency). Asia-Pacific revenues increased 14% (7%, adjusting for currency) to $5.9bn. OEM revenues were $806 million, up 27% compared with the 2009 third quarter.

Results detail

Parsing Apple's earnings results with Vijay Rakesh, of Sterne Agee, and CNBC's Jon Fortt:

Parsing IBM's earnings results with Ted Moore, of Fifth Third Asset Management: