The long wait for Apple's (NASDAQ:AAPL) new iPhone -- and possibly even more -- may finally be over. Sources tell AllThingsD that the consumer-tech giant will host a media event on Sept. 10 to peel back the curtain on its latest smartphone.

It's about time!

Historically speaking, Apple has introduced a new iPhone around every summer. The iPhone 5 was announced on Sept. 12, 2012, and rolled out to retail nine days later. However, given the way Apple's stock has fallen since the last new iOS phone hit the market, the pressure is clearly on Apple to deliver something special.

Apple shares hit $705.07 on Sept. 21, the morning the iPhone 5 was introduced. The stock has fallen more than 35% in that time.

A few things have gone well for Apple. Outside of Google's (NASDAQ:GOOGL) growing Android reach, companies that were hoping to replace Apple as the silver medalist in this growing industry have fallen short.

Microsoft (NASDAQ:MSFT) has thrown billions at its updated Windows Phone 8 mobile operating system. Lumia devices are selling well, but the software giant's market share, according to industry tracker IDC, has grown from 3.1% to only 3.7% over the past year. 

Things have only fared worse for BlackBerry (NYSE:BB). It dusted off an updated operating system in January, but BlackBerry's market share has continued to fall sharply. Reports surfaced on Friday that the smartphone pioneer's board is thinking about going private. If so it's another concession that the turnaround process will take time.

With BlackBerry fading and Windows Phone failing to catch on, Apple should be doing well -- but it's not. The growing popularity of Android and the proliferation of cheaper Android smartphones with slick features and larger screens have forced Apple into carrying older models at lower price points to compete on price and scrambling so as to keep up on specs. Even with average selling prices and margins falling, Apple's global share of the smartphone market, according to IDC, has declined from 17% to 13% over the past year.  

The pie is growing to the point where Apple's thinning slice is still larger in absolute unit numbers, but there's also a problem in that roughly half of the iPhones being sold these days are iPhone 4 and iPhone 4S devices, which came out two and three years ago. Are iPhone buyers strapped for cash to the point that they want to save $100 on a 2011 phone or $200 or a 2010 relic, or is the iPhone 5 just not enough of an upgrade to make the premium worthwhile?

Next month's new iPhone will have to change that. It will have to be cool. It will have to raise the bar in a greater way than last September's incarnation. It will have to be the model worth buying, pushing average selling prices and margins higher again to the delight of frustrated stakeholders.

The next few weeks will be loaded with speculation about what we'll get out of Cupertino. It is crucial for Apple to get it right. 

The last thing Apple wants is to look in the mirror in a couple of years and see BlackBerry staring back.

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