Apple Inc. (NASDAQ:AAPL) will likely start selling a low-cost iPhone in the December quarter, according to well-known Piper Jaffray analyst Gene Munster. He believes that the device will add 12 million units to the company’s December quarter results.

Apple analyst Gene Munster

Munster previews results from Apple

Tomorrow Apple Inc. (NASDAQ:AAPL) will release the results from its June quarter, and Munster is in line with consensus, expecting 26 million iPhones to have been sold during the quarter. That number is flat with last year’s June quarter iPhone sales.

Munster expects Apple Inc. (NASDAQ:AAPL)’s September quarter to only see sales of 24 million iPhones, which is significantly lower than the same quarter last year when there were 26.9 million iPhones sold. According to Munster, this September quarter estimate depends on the company shipping its iPhone 5S in the second half of September.

Apple’s place to improve around the holidays

According to Munster, the fourth calendar quarter of the year is where things will pick up for Apple Inc. (NASDAQ:AAPL). He’s expecting the release of a low-cost iPhone to enable the company to sell 62 million iPhones—well ahead of Wall Street consensus, which is for 50 million iPhones during the December quarter. However, it should be noted that the Wall Street consensus does not make the assumption that there will be a low-cost iPhone rolled out in time for the holidays. This is why Munster has added 12 million iPhones onto his estimate.

He did say that 62 million might be a bit off though if cannibalization from Apple Inc. (NASDAQ:AAPL)’s low-cost iPhone is a problem. He assumed a 50 percent cannibalization factor from the release of the lower priced model. He said that might be too aggressive since we don’t know when the device will be out. He said if they add in the cannibalization factor, it would bring his core estimate for iPhones in the fourth quarter to 56 million. It’s also important to note that his estimate includes expectations that the iPhone 5S will be out by the end of the year.