• The S&P 500 and Nasdaq closed higher on Monday.
• Apple's first version of Apple Intelligence has been released.
• Delta has hired a lawyer to seek damages against CrowdStrike and Microsoft.

Here are five key things investors need to know to start the trading day:

1. Ticking higher

The S&P 500 and Nasdaq Composite inched higher on Monday as the busiest week of earnings season kicks off. The broad market index advanced 0.08% to close the session at 5,463.54, and the Nasdaq Composite gained 0.07% to finish at 17,370.20. The Dow Jones Industrial Average, on the other hand, moved lower, dropping 0.12% to end at 40,539.93. This week, Microsoft, Meta Platforms, Apple and Amazon are all slated to report their quarterly results. Their performance post-earnings will help reveal whether megacap technology stocks can rebound from last week's losses. Follow live market updates.

2. Taste test

The first version of Apple Intelligence is here. On Monday, Apple released the AI features in the developer beta of iOS 18.1, which is only available to registered Apple developers at the moment. The company's developer program costs $99 a year. In order to gain access, users will also have to sign up for a waitlist in the settings app after updating. Apple Intelligence is scheduled to be released to the public later this year, but this 18.1 version suggests it won't be released alongside the new iPhone models that are expected to run iOS 18. The company also said Monday that the AI models used for its system were pretrained on Google-designed chips, signaling that companies are scoping out alternatives to Nvidia.

3. Lawyered up

Delta Air Lines is seeking damages following the CrowdStrike outage this month. The airline hired attorney David Boies to seek damages from both CrowdStrike and Microsoft. The lawyer is known for representing the federal government in its Microsoft antitrust case, as well as for successfully challenging California's ban on gay marriage. No suit has been filed just yet, but Delta plans to seek compensation from both companies, according to CNBC's Phil LeBeau. The decision comes after CrowdStrike's software update earlier this month led to an outage of Microsoft systems and the cancellations of thousands of flights. The event cost the airline an estimated $350 million to $500 million.

4. Second-half blues

The second half of the year is expected to be a challenging one for General Motors, Ford and Stellantis. U.S. auto sales are expected to slow during the second half of the year, projecting about a 1.3% increase compared with 2023. The first half saw a 2.9% year-over-year increase. GM is planning to increase production of EVs in an attempt to make the vehicles profitable, which is one reason why its earnings are set to be lower in the second half. Ford's guidance is down to reflect higher warranty costs. For Stellantis, CEO Carlos Tavares has said that its U.S. operations were being impacted, due to mistakes made over vehicle inventory levels, manufacturing and sales strategies. This all comes as uncertainty persists around EV adoption.

5. Missing the mark

McDonald's is shifting its focus over how to recapture customers with deals. Following second-quarter earnings results that missed Wall Street's expectations, the company's U.S. president, Joe Erlinger, said in a memo obtained by CNBC on Monday that McDonald's contended with selling diners based on affordability. The president also said that he expects "industry and competitive challenges" to persist for the remainder of the year and encouraged operators to look toward building momentum for 2025. "Reversing the narrative and re-establishing our position as the leader on value and affordability is possible, but it cannot be done overnight," he wrote. "It will happen through sustained and coordinated actions that show the customer we're on their side."

— CNBC's Pia Singh, Jesse Pound, Kif Leswing, Jordan Novet, Ari Levy, Michael Wayland, Kate Rogers, Amelia Lucas and Ece Yildirim contributed to this report.

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