Iphone

Source: Apple.

September is just around the corner, which means Apple's (NASDAQ:AAPL) annual iPhone extravaganza is, too. The current rumor is that the unveiling event will take place on Sept. 9, with pre-orders beginning on Sept. 11 ahead of a Sept. 18 launch. Here's what the Mac maker's most important product lineup could look like after the refresh.

"S" is for speed
This year will mark an "S" cycle for Apple, and the iPhone 6s and 6s Plus are no-brainers. Don't expect any major hardware redesigns, as Apple will probably focus on incremental improvements under the hood, like a faster A9 processor and maybe some new software features within iOS 9. That said, Apple is widely expected to upgrade the hardware in the form of Force Touch.

The current 6 and 6 Plus upgrade cycle has been so incredibly strong that Apple will face a tough comp this year, which could even lead to the first time in the company's history where it posts negative iPhone unit growth. Still, even if it does, investors shouldn't worry too much about it.

To 6c or not to 6c, that is the question
Starting in 2013, Apple started releasing two new iPhone models per year, up from its historical practice of one new model per year. That year, it was the iPhone 5c and 5s that launched side by side. While the 5c's pricing came in a bit higher than investors were expecting at the time, it had a strategic place within the lineup. In 2014, it was the 6 and 6 Plus that marked Apple's move to larger displays -- 4.7 and 5.5 inches, respectively. These four models comprise Apple's current lineup. Since carrier subsidies are on the way out, here's the portfolio in full retail prices:

Model

Starting Price

iPhone 5c

$450

iPhone 5s

$550

iPhone 6

$650

iPhone 6

$750

Source: Apple.

There have been some reports suggesting that a third iPhone could be in store for the 2015 cycle. The presumed iPhone 6c would be an update to the 5c that currently sits on the low-end of Apple's pricing spectrum. China Times says that Foxconn is ramping up in preparation for a November launch for the 6c, although Evan Blass, the reputable former supply-chain leaker who used to run @evleaks, believes all three will "arrive concurrently."

If Apple goes with an iPhone 6c, it could discontinue the iPhone 5 and 5s that share the same design, which also means it could retire the associated manufacturing equipment and simplify its cost structure. Maybe this will be the lineup by the end of next month:

Model

Starting Price

iPhone 6c

$450

iPhone 6

$550

iPhone 6s or iPhone 6 Plus

$650

iPhone 6s Plus

$750

Source: author's estimates.

Unless there's a curve ball...

5c: The "C" is for China?
Remember when the iPhone 5c packaging and name was leaked before the official announcement, which triggered a wave of speculation as to what the letter stood for? Depending on what strategy Apple takes with the 5c, the "c" could stand for "China."

Sure, that idea was already suggested years ago, but it's a bit more potent now. Consider the iPhone 4. Even after Apple discontinued the iPhone 4 in developed markets as it naturally cascaded down the price points, Apple still sold the aging device exclusively in emerging markets such as China to address even lower price points. Better yet, it sold a lot of them. The iPhone 4 is the perfect example of how Apple keeps around a relatively older product at even more affordable prices in an attempt to compete with low-cost vendors.

Even though Apple's most affordable older devices are more expensive than the most expensive and newest handsets from low-cost Chinese OEMs, it's better than nothing.

Evan Niu, CFA owns shares of Apple. The Motley Fool owns and recommends Apple. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.