One of the biggest days of the year is coming up for Apple Inc. (AAPL) watchers and fans.

The tech giant's annual Worldwide Developer Conference kicks off on Monday with a keynote address from CEO Tim Cook, and rumors have been swirling about what upgrades and new products the smartphone giant will announce. Here's what could be on the horizon for Apple:

TheStreet will be live blogging Tim Cook's WWDC keynote address on Monday, June 4 at 1 p.m. ET. Please check our home page then for more details.

1. A new iPhone SE

One of the biggest announcements expected at WWDC 2018 is the announcement of a new iPhone SE. Apple first released the smaller, more affordable version of the iPhone in 2016 for $399, in part as a way for Apple to sell more phones in emerging markets such as China and India. By the end of 2016, the iPhone SE made up almost 10% of total iPhone sales for the year, according to research firm IHS Markit.

The rumor mill has it that the new SE will look like an iPhone 5, have an Apple-designed A10 processor -- first introduced with the iPhone 7 -- and feature a notch like the iPhone X. Along with its lower price, the new iPhone SE is expected to have a smaller 4.5-inch screen and might even have wireless charging capabilities, which was first introduced with the iPhone 8 and X.

"The iPhone SE has been on a separate upgrade calendar from the higher-end iPhones and could be updated at WWDC," KeyBanc analyst Andy Hargreaves wrote in a note on May 30, adding that he does not anticipate an updated iPhone SE to change the firm's unit sales estimates.

2. A new mobile operating system

Many are expecting that Apple will upgrade its mobile OS from the current 11.4 to iOS 12. The previous release, iOS 11, was first announced at last year's WWDC, and was released after the keynote that introduced the iPhone X back in September. The new iOS is expected to allow for cross platform development so that mobile app developers can more easily apps for Macs as well.

Apple is also reportedly planning a new initiative as part of the new operating system around "Digital Health," which will include tools to monitor overall time spent on the phone and various apps. The tools are a response to concerns about smartphone addiction, and mirror some new features being built into Android phones that were announced at Google's own I/O developers conference in early May. "It's a balancing act for Apple," DA Davidson analyst Tom Forte said in an interview with TheStreet, adding that "I don't think Apple needs to play the role of a parent."

Siri may also get an upgrade in voice and other functions to be more on par with Amazon's (AMZN) Alexa and Alphabet's (GOOGL) Google Home. It's also rumored that Animojis will expand from just being available in iMessages to FaceTime, and that Apple's Stocks will get a redesign.

3. More augmented reality features

Apple dipped its toe into augmented reality with the newest iPad, which featured upgraded sensors and cameras to offer an improved AR experience. Now the rumor is that the company will go all-in by releasing AR/VR smart glasses, for now codenamed T288. Rumblings about the headset first came out in late 2017 and they're not speculated to be released until 2020, but Apple may show off what's to come with respect to its AR efforts.

Apple's stock was up 1.6% to $189.84 Friday afternoon. Shares have increased 12% since the beginning of the year.

This article was co-written by Oscar Gonzalez.

Apple, Amazon and Alphabet are holdings in Jim Cramer's Action Alerts PLUS member club. Want to be alerted before Jim Cramer buys or sells AAPL, AMZN or GOOGL? Learn more now.

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