It may be a misnomer to call anyone in retail a ¬“winner” right now, when stay-at-home and social-distancing measures have shut down hundreds of thousands of U.S. stores and threatened consumers’ spending for the foreseeable future.

But look at the few chains that have managed relatively well in this chaotic time, and you’ll gather clues about what it will take to come out ahead in the industry, both now and long after the virus has been contained.

Walmart’s U.S. sales reportedly jumped 20% in March as people stocked up on essentials—further boosted by a 190% increase in monthly downloads of its online grocery app, according to data tracker App Annie. Nike kept its China business from stalling, thanks to a fitness app that helped homebound consumers do quarantine workouts. And Lululemon Athletica has even reopened a few North American stores, not to serve walk-in customers, but to use inventory to fill online orders more quickly.

What these cases make clear is how central the full integration of stores and shopping technology has become to big retailers’ health. “The retailers that were already doing it successfully are the ones that are going to recover much more quickly,” says Kimberly Becker, senior research director with Gartner. And in a future when shoppers are likely to be skittish about staying long in any store—if they visit at all—only the tech-savvy chains will survive.

The big-box retailers proved their mettle during the rush on stores in March, as Americans stripped shelves of essentials like toilet paper and baker’s yeast. While lengthy waits for delivery were thwarting many e-commerce shoppers, Target and Walmart succeeded by offering drive-up retrieval for online orders through their apps. (This will become increasingly important now that both chains are limiting the number of shoppers allowed in stores at any one time.)

And the fact that the chains now hold much more of their e-commerce inventory in stores than they once did helped them avoid shortages. “Because we’re using stores as local fulfillment hubs, we’ve been able to handle sustained, holiday-like online volumes,” Target chief operating officer John Mulligan tells Fortune.

Crisis-related changes in shopping habits have also accelerated a less-is-more approach to product selection. To keep shelves well-stocked, retailers have worked closely with suppliers to limit the variety of sizes, colors, and flavors of all sorts of goods, focusing only on those most consistently in demand. Unilever, for example, said last month it would concentrate mostly on large sizes of its products, like 30-ounce jars of its Hellmann’s mayonnaise, to speed up production and distribution.

Retailers like Walmart and supermarket giant Kroger have long been shifting in this direction, opting to devote more shelf space to bestsellers rather than stocking 50 varieties of the same detergent. “There’s been a slow bleed of taking out the stuff that’s just another color or another flavor and isn’t pulling its weight,” says Laura Kennedy, lead consumer and retail analyst at CB Insights. Increasingly, if you crave a company’s seventh-bestselling sandwich cookie, you’ll have to find it on the Internet.

Technology is helping retailers wring more revenue out of their inventory. Lululemon has invested heavily in RFID (radio-frequency identification) tech, enabling it to know in real time where every hoodie or sports bra is, whether at a distribution facility or in a store. That’s making it much more efficient in filling online orders from physical stores, at a time when e-commerce is its only source of income. “The race is, How much cash can you get out of inventory that’s stuck in stores today?” says Nikki Baird, vice president of innovation at retail tech firm Aptos.

Stores that can precisely track inventory are also helping their customers: The best apps can tell shoppers which items are in stock in what store and where in that store, an appealing idea for customers who don’t want to linger. (Walmart and Target have made big strides in this arena too.)

Retailers’ tech successes aren’t focused solely on logistics and efficiency: They can also keep customers interested in a brand. After most of its 7,000 retail locations in China were closed, Nike made the premium version of its workout-on-demand Nike Training Club app—which is seamlessly integrated with Nike’s e-commerce—available for free there. As use of its apps surged, Nike’s digital sales rose 30% in China during the country’s six-week lockdown, and business in stores bounced back quickly once they reopened. Nike is using the same playbook in North America now. “We know that consumers need to maintain their mental and physical health,” says Heidi O’Neill, Nike’s president of consumer and marketplace.

Still, even after the crisis has passed, no one expects shoppers to quickly return to their old comfort levels in physical stores. Some upgrades Nike has implemented, like self-checkout and contactless payment systems, seemed like nice-to-haves before the coronavirus; after stores reopen, they’ll be must-haves. “The investments you made are going to be ever more meaningful when customers come back,” says O’Neill. 

A version of this article appears in the May 2020 issue of Fortune with the headline “Next-gen apps to ease new anxieties.”