Sonny Dickson

Buyers of Apple's much-rumored, low-cost iPhone might not be able to chat with Siri.

Reportedly named the 5C, the cheaper iPhone may jettison certain features, such as Siri, analyst Gene Munster stated in an investors note released Monday night. Unveiled in 2011, Apple's voice assistant doesn't support prior phones, such as the iPhone 4 and 3GS.

Munster said he believes the 5C will sell for $300 on average and roll out in September. As such, he said it would make sense for Apple to retire the iPhone 4S and position the iPhone 5C as the low-end model in Apple's portfolio.

And what of the iPhone 5S?

Munster's expectations for the next-gen iPhone are "minimal." He said he believes the new phone will feature a fingerprint sensor as a way to unlock the screen. But he doesn't think the sensor will allow users to tap into secure mobile payments. Instead, he said he sees such a feature debuting in the next version of iOS in 2014.

Munster said he believes that the low-cost iPhone could steal around 25 percent of sales from its more expensive, bigger brother. But that figure is down from his previous estimate of a 50 percent cannibalization rate.

Peering into his crystal ball for next year, the analyst thinks the iPhone 6 will launch in early to mid-2014 with a screen size of 4.5 to 5 inches.