Apple (AAPL 1.27%) is "currently aiming" for a product launch event on March 15, according to 9to5Mac's Mark Gurman. And when Gurman calls it, Apple rumors are about as credible as they get. His track record with information on events and products ahead of their release is solid.

Apple store. Image source: Apple.

What exactly is Gurman expecting at the event? Two new products: an iPad Air 3 and a smaller iPhone. Here's what there is to know about the two products, along with a bit of context about why they may matter to investors.

iPad Air 3
Apple will give its 9.7-inch tablet line its "first significant upgrade" since the iPad Air 2 launch in October 2014, Gurman predicts. He says the updated tablet will take some cues from the iPad Pro, including enhanced speakers and a Smart Connector, or Apple's new interface that connects a keyboard to the iPad.

The company may be hoping the fresh update to its iPad line could moderate declining sales in the category. Apple's iPad business, which accounted for about 9% of total revenue in its most recent quarter, has been declining on a year-over-year basis for nearly two years. In Apple's most recently reported quarter, iPad unit sales were down 25% from the year-ago quarter and iPad revenue was down 21% during the same period.

By beefing up its tablets with better speakers and Smart Connectors that enable them to connect to keyboards, Apple is increasingly blurring the lines between Macs and iPads. While the two products are still distinctly from each other, they're becoming similar enough for a small yet growing group of users who may opt to replace their notebooks with tablets. The most recent update for the iPad Air may give investors more insight into the company's evolving vision for tablets.

iPad Pro. Image source: Apple.

A smaller iPhone
In addition to the iPad Air update, Apple will "reinvigorate the 4-inch iPhone screen size" with the introduction of a new iPhone with a 4-inch display, according to Gurman. It will sport Apple's A9 chip, improved rear- and front-facing cameras, support for Live Photos, and Apple Pay, he says.

This smaller iPhone, which Gurman believes will start at $450, will improve the company's offering at this important price point. Apple's iPhone 5s, which currently also starts at $450 and also sports a 4-inch display, will be retired as this new iPhone takes its place, Gurman says.

Apple CEO Tim Cook emphasized the importance of selling iPhones at difference price points during the company's most recent earnings call, noting that the iPhone 5s is continuing to sell well.

iPhone 5s. Image source: Apple.

A March launch for an iPhone would be out of the norm for the company. Apple has historically spaced out its iPhone launches by a year, introducing them every fall. But the unusual timing makes sense. With Apple now guiding for a year-over-year decline in total revenue for its current quarter, a mid-cycle iPhone launch could potentially help Apple's iPhone segment return to growth later in the year.

For now, it's looking like the event will probably take place on Gurman's predicted date. Even BuzzFeed's John Paczkowski -- another journalist with a solid track record with Apple rumors -- has confirmed the speculation for the March 15 date.