CHICAGO—Walmart said on Thursday it would give nearly half its U.S. employees free Samsung phones by the end of the year so they can use an app the company has developed to manage shifts, clock in, and stay in “constant communication.” The world’s largest retailer, which employs nearly 1.6 million people in the United States, said more than 740,000 workers would receive Samsung Galaxy XCover Pro smartphones, cases, and protection plans. Currently, most people share company devices. Walmart declined to share financial details, but the phone sells at $499.99 on Samsung Electronics’s website. It is common for big companies to strike heavily discounted deals with carriers and device makers when buying corporate phones in bulk. The retailer, which tested the project earlier this year, said it would not be able to see personal data. It will be able to see work emails, installed work apps, web history on the phone’s …