Reports that Apple plans to launch an iPhone 4S and an iPhone 5 at the same time, providing both high- and low-end options for customers are short of the mark, an analyst has claimed.

BMO Capital's Keitch Bachman said that he believed Apple would launch an iPhone 4S but keep the iPhone 3GS as the low-end option, contradicting what Deutsche Bank's Chris Whitmore claimed in a note to investors on Monday morning.

Bachman's comments, reported in the Barrons blog on the Wall Street Journal site, state explicitly: "We believe that the 3GS will be the low-end iPhone".

Deutsche Bank's Whiting said on Monday: "With Nokia and RIM struggling, the time is right for Apple to aggressively penetrate the mid range smart-phone market to dramatically expand its total addressable market and market share."

Whiting believes that there are potentially 1.5bn customers worldwide that would be interested an iPhone 4S that came unlocked with a pre-pay voice plan.

Bachman does believe that there will be an iPhone 4S, though, as that will be the model launched "late in the September quarter". In other words, there will be no iPhone 5 launched in September.