• The UAW could expand its strikes.
• Instacart's IPO is priced at $30 a share.
• Consumer say they're planning to spend less.

Here are the most important news items that investors need to start their trading day:

1. Feeling flat

Stock futures were trading slightly higher Tuesday coming off of a relatively flat session. Futures tied to the Dow Jones Industrial Average rose 0.13%, while S&P 500 futures and Nasdaq 100 futures both gained 0.15%. In Monday's trading session, all three major averages rose less than 0.1%. Six of the 11 major S&P sectors finished Monday's session positive, led by energy with a 0.7% gain. Consumer discretionary was the worst-performing sector and finished about 1% lower. The Federal Reserve will start its two-day meeting on Tuesday, which investors will be watching closely. Follow live market updates.

2. Strike season

The so-called "summer of strikes" is entering a new season. With thousands of United Auto Workers members walking off the job and writers and actors continuing to strike in Hollywood, unions have found a louder voice in the high-inflation era. The Labor Department reported that August saw the equivalent of 4.1 million labor days lost, the result of 20 large stoppages and the most for a single month since August 2000. So far, the UAW stoppage has impacted just a small portion of the workforce at three key plants, with limited implications for the broader economy. But that could change if more workers are called to walk out. Late Monday, UAW President Shawn Fain said the union would do just that and expand the strikes if the sides don't make "serious progress" in negotiations by noon ET Friday.

3. Spending less

Americans plan to continue cutting back on spending throughout the all-important holiday season, according to a poll fielded on behalf of CNBC by survey company Morning Consult. The vast majority of adults (92%) said they have reduced their spending over the past six months. Looking ahead, more than three-quarters (76%) said they plan to cut back on spending for non-essential items and 62% expect to cut back on essential items "sometimes" or "more often" over the next six months, according to the poll. The most common areas where consumers said they're cutting back have remained consistent, with the top three coming in as clothing and apparel (63%), restaurants and bars (62%), and entertainment outside the house (56%).

4. Shiny new Apple features

Apple released its biggest software update of the year on Monday. Users don't need a brand new smartphone to get the features, as iOS 17 is available to anyone with an iPhone released in 2018 or later. This year's changes include improvements to some of the most used apps, including the Phone app, Messages and Safari. iOS 17 introduces "contact posters" that allow users to select a picture and font to change how they appear when they call other people's iPhones, as well as a better autocorrect. It also has a new iMessage interface, roadside assistance and automatic "got home safe" notifications, among other things.

5. Instacart pricing

Grocery delivery company Instacart priced its long-awaited initial public offering at $30 a share on Monday. That's toward the top of the expected range and gives the company a value of about $10 billion on a fully diluted basis, a significant difference from when it was valued at $39 billion in early 2021 at the height of the Covid pandemic. The stock is set to debut on the Nasdaq on Tuesday under the ticker symbol "CART." It's raised money from prominent venture firms like Sequoia Capital and Andreessen Horowitz, along with big asset managers Fidelity and T. Rowe Price. It will be the first notable venture-backed tech company to hit the U.S. public market since December 2021.

— CNBC's Samantha Subin, Jeff Cox, Michael Wayland, Harriet Taylor, Kif Leswing and Ari Levy contributed to this report.

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