New iPad Pros
Apple is expected to announce at least one new iPad Pro on Tuesday. The standard 9.7-inch iPad was refreshed in March of this year, but Apple so far hasn't updated last year's 12.9-inch iPad Pro or the 10.5-inch iPad Pro.
According to well-sourced TF International Securities analyst Ming-Chi Kuo, who correctly predicted this year's iPhone lineup, Apple will launch a new iPad Pro with an 11-inch screen to replace the 10.5-inch model. Bloomberg said in August that Apple has multiple iPad Pros in the works, so it's possible a new 12.9-inch model could be coming, too.
The new iPads are expected to offer Face ID, which lets you unlock the iPad by looking at it, instead of a home button with a fingerprint sensor. This should allow for a larger display that covers almost the entire face of the iPad.
New MacBook Air
Kuo said in March that Apple has been working on a new, cheaper MacBook Air to replace the current model. While the 13-inch MacBook Air has been upgraded with new processors in recent years, Apple still hasn't redesigned the computer or added the sharper Retina screen that's found in its other MacBook computers. Bloomberg echoed Kuo's note in August, adding that it expects Apple to replace the current low-res screen with a sharper one.
New Mac Mini
Apple is also expected to announce a new professional version of the Mac Mini, according to Bloomberg. The Mac Mini, which is a small desktop computer that doesn't ship with a display, hasn't been updated in more than four years. A Pro model will offer "new storage and processor options," according to Bloomberg. That suggests the latest Intel processors and faster, but more expensive, solid-state storage may be included.
Apple might use the event to finally announce the availability and price of its AirPower wireless charging system. AirPower was originally announced in September 2017. It's a pad that will let people charge an iPhone, AirPods and the Apple Watch wirelessly at the same time. But Apple removed all mention of AirPower from its website in September, and didn't discuss the product at all during its September 2018 iPhone event, leading insider John Gruber to speculate it might have been canceled entirely.
But if Apple does announce AirPower, there's still room for the company to announce a wireless charging case for AirPods, which would let users wirelessly charge AirPods by dropping them either on the pad or any other wireless charger that supports Apple's iPhones. Kuo said in December 2017 that Apple is planning a new set of AirPods, though little has been discussed about them since then. Bloomberg said in June that Apple is also planning over-the-ear headphones for 2019, so don't expect to hear much about them Tuesday.