Today kicked off the first trading day in September, and this month will see four very major tech events that will rock the mobile sector. Here's what investors need to keep an eye on in September.

Sept. 5: Microsoft and Nokia
Lovebirds Microsoft (Nasdaq: MSFT) and Nokia (NYSE: NOK) are hosting an event tomorrow, and will assuredly unveil the newest offspring borne of their union. Microkia should be taking the wraps off of Nokia's first Windows Phone 8 device. We're probably looking at two models here: the Lumia 820 and Lumia 920.

The Lumia 820 reportedly sports a 4.3-inch display, while the Lumia 920 will go up to a 4.5-inch display and come with PureView, Nokia's latest cameras, which can pack up to 41 megapixels. The sensor in the 920 will probably be just 8-megapixel, but PureView is now more of a brand than a specific sensor. Both devices are also going to feature wireless charging capabilities, made possible by an inductive charging pad.

We'll see if Microkia gets any type of first-mover advantage here.

Sept. 6: Amazon
Contestant No. 2, come on down! We're talking about none other than Amazon.com (Nasdaq: AMZN), which will reveal the second iteration of its popular Kindle Fire tablet in just a matter of days. Ahead of the event, Amazon has announced that it has officially sold out of the first-generation model: it's run through the rest of its remaining inventory and production has been discontinued.

The device is supposed to lose some weight and will also likely be slightly redesigned. It should get an upgraded display to 1,280 x 800 pixels, matching Google's Nexus 7, as well as a beefier quad-core NVIDIA Tegra 3 processor, again matching Big G. The company has supposedly tapped Nokia to provide the mapping service, much like the Finnish company powers Bing maps.

CNET reports that Amazon is launching two separate 7-inch tablets, instead of the rumored 10-inch flavor. This could potentially be two different storage configurations, or maybe one is a cellular data-equipped model. Or one could be an ad-supported model, available at a lower price point if consumers are willing to look at ads.

Sept. 12: Apple
The elephant in the room is, of course, Apple (Nasdaq: AAPL). All eyes will be on the iPhone maker on Sept. 12, even though Apple has yet to officially confirm or send out save-the-date cards to the media. This year will see the most meaningful upgrade to the iPhone in several years, including a redesigned body and a boost in data speeds up to 4G LTE.

Apple has already seen iPhone unit sales slow in anticipation of the new models, a victim of Apple's nonstop rumor mill. Analysts and investors alike already have lofty expectations of the new model, with some estimates as high as 250 million units sold throughout its life cycle, which would double lifetime iPhone unit sales.

The launch date is pegged at Sept. 21, just nine days later, with wireless carrier partners reportedly instituting vacation blackouts, as they'll need all the hands they can get.

Sept. 18: Intel and Googorola
Chip titan Intel (Nasdaq: INTC) and gadget maker Motorola announced this January that the two would collaborate on an Atom-powered smartphone. Since then, Google closed its acquisition of Motorola and Intel has continued to slowly edge into the smartphone space with a handful of spots, but this will likely be the highest-profile smartphone launch for Intel's Atom processors.

The pair is now hosting an event later this month for "an exciting announcement" that promises to "take you to the edge." The Atom-powered smartphones released so far this year have been in other markets like India and Europe. Even though this event will be in London, I'm half expecting the duo to unveil a model targeting the U.S.

This year is an important one for Intel's mobile strategy, as it hopes to mitigate the dominance of ARM Holdings-based chips, which have proliferated throughout mobile devices. Hooking up with Googorola will pay off, since Google has already optimized Android for Intel's x86 chips and Motorola can apply its hardware specialties.

This promises to be one powerful triad.

On your mark
Mark your calendars accordingly, investors. It's going to be a jam-packed month in the world of mobile computing.

Of the companies making big splashes this month, Apple's launch will have the most meaningful impact on the market, which is why you should read up on the iPhone maker before it unleashes the next iPhone onto the world. The Fool's brand-new premium research report lays out every piece of Apple's potential upside and downside for you, and comes with free regular updates. Click here to get started!