Was just thinking with the introduction of a cheaper iPhone couldn't apple take that design make it out of aluminum. The S models have always been an upgrade from the model that came before it the intro of a cheaper model would negate the need for a S model.
I'm not sure how the plastic iPhone negates the "need" for an S-model iPhone. First off, I don't necessarily accept that there is a "need" for an S-model phone at all; it's simply part of an established refresh cycle for the iPhone. The S-cycle allows Apple to continue to use the manufacturing established for the shell of the iPhone while refreshing the internal components; it's a cost-savings measure to present a new phone without having to completely reinvent the wheel. The S-cycle is not specifically designed to reinvent the older model iPhones as cheaper alternatives anymore than the 4 or 5 models were; it's just a natural consequence of introducing a new model phone.
The plastic iPhone is being designed to meet a specific market that the iPhone doesn't currently reach. Even the "cheaper" older models are more expensive than a lot of the plastic Android alternatives that are crushing that market. Apple is taking a gamble that they can, with a new manufacturing process, meet Android on an even playing field with their new phone. I don't seen any reason why that would or should impact the "premium" iPhone line, so I fully expect that the 5S is going to stick to that refresh cycle.
Apple could've used the 5 as a bridge device and make a whole new iPhone. it could feature a bigger screen more powerful while offering the cheaper version with last years specs and a plastic shell. In one fell swoop cut production cost of producing the 5 while increasing their margins at the same time with the new model.
This is 100% speculation based on nothing other than what you
want to happen. There's no reason to suspect that what you're guessing at is true; it's much more logical to assume that nothing is changing in regard to the S-cycle. Not only this year will they be cutting production costs of the 5 by moving to a plastic shell, they can continue to manufacture the premium 5 casing while refreshing the internals and
really increasing their margins. From a cost-perspective it makes a lot more sense to keep the current 5 housing for the 5S as opposed to investing in the manufacturing process for it and then abandoning it in a year just to surprise fanboys.
I'm not saying that you're wrong; you absolutely could be right. But at this point there's no reason to suspect that what you're saying is true; it's wishful thinking at best. I have a hard time believing at this point that if a new iPhone 6 model had been developed and were being manufactured that, like the plastic iPhone casing, we wouldn't have seen anything by now. Your comparison to the MacBook Pro doesn't really compute; Macs aren't nearly as popular as iPhones and the attention paid to them by the general public is miniscule compared to the iPhone. Also, slipping a MacBook screen or unibody casing off the manufacturing line is a whole different logistical problem than just slipping an iPhone casing into your pocket.
Finally, there has been no rumbling at all from analysts, insiders, or others that an iPhone 6 is on the horizon. That's just not realistic. If there was even a hint of an iPhone 6 coming instead of a 5S, insiders would be climbing all over each other to get that scoop. I think that evidence clearly points to an S-cycle release, which we should all be expecting at this point. Hoping for anything else is really just going to leave you disappointed.
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I think the budget iPhone will be the 5S and the premium phone will be the 6 (regardless of big design change or not). This way Apple can stop iPhone 4S and 5 sales and have better margins with the budget 5S and the premium 6. This would result in an S and regular model every year which would make them easy to differentiate.
Regardless of what they call it, it will be an S-cycle "type" of release at best. I don't believe that Apple is going to reinvent the body style of the iPhone every year.