The shift to smartphones shows no sign of slowing down.

In the U.S., visits to websites via smartphones have increased 69% in the past three years, according to a new mobile report Adobe Analytics released this week at the Mobile World Congress event in Barcelona, Spain. The report analyzed data from 1.7 trillion  visits to 16,000 websites across devices and 130 billion app launches from more than 1,000 apps between January 2014 and January 2017.

The traffic gain for smartphones was at the expense of desktops and tablets, as U.S. desktop traffic decreased 23% since January 2014, and U.S. tablet traffic decreased 19%, according to Adobe. This trend is mirrored worldwide, according to the report.

Despite retailers discounting tablet prices, the device’s share of web traffic is not increasing, says Becky Tasker, senior managing analyst at Adobe Digital Insights. In fact, on Black Friday 2016, retailer discounts on tablet devices were  92% deeper  than on the Friday after Thanksgiving in 2015, according to the report. Tablets were on average reduced by 25% of their cost, Adobe says. For instance, Amazon.com Inc. during the holidays sold the Kindle Fire 7-inch tablet for $40; its normal price is $50. When the product launched in 2011, it was $199.

“Despite steep discounts [on tablets] this past season, their share of traffic decreased or stayed flat in every country around the world,” Tasker says.

Retailers should take note of these trends, Tasker says. While web merchants may already know half or more of their traffic stems from smartphones, they need to be sure they always cater to those consumers, she says.

“Images must be sized appropriately for smaller screens with pinch-and-zoom capabilities, along with more personalized recommendations and offers,” Tasker says. “On the cart page, a critical conversion tool, shoppers should be able to easily move back and forth between the product pages, with better integration of all available payment methods.”

While smartphone traffic surges, the honeymoon with mobile apps is over. App installs in the U.S. have decreased 38% since December 2014, and the number of times a consumer launches an app decreased 28% within this time period.

“Consumers are becoming more selective in the apps they choose to use, and may jump ship if a competitor offers a better experience,” Tasker says.

Adobe expects the United Kingdom  and France to experience a similar decline, although app usage in those countries has only dropped 4% since December 2014.

“Double-digit declines in both app installs and launches means that brands have a large mobile audience but need to focus on retention,” Tasker says.

Tasker, however, notes that traffic to websites and apps typically increases in January when compared with December. January 2017 is no different with an 8% increase in app installs and a 7% increase in smartphones traffic compared with December 2016, according to Adobe.

“In the new year, consumers are downloading more apps to test out or re-engaging with existing ones,” Tasker says.

Retailers should capitalized on this opportunity to re-engage with shoppers, she says. For example, a retailer could analyze what a shopper bought in December and recommend a related product. For instance, if a consumer bought boots in December the retailer could offer her a discount on a pair of boot socks, Tasker says.

The report also notes that overall U.S. web traffic is plateauing as the country is no longer bringing new users to the internet. Other countries, such as China and Brazil, however, are adding new internet users as smartphone usage continue to grow. This is also true in developing nations. For example, smartphones’ share of traffic grew 43% year over year in Argentina, according to the report.

The report also found that Google’s accelerated mobile pages (referred to as AMP) is catching on. AMP is an open-source framework that allows businesses, including retailers, to build lightweight mobile pages that load as fast as possible on smartphones. Most businesses that are shifting to AMP are publishers, although online marketplace eBay Inc. is experimenting with the feature. On average, top U.S. publishers have 7% of their web traffic routed through Google AMP, according to the report.

Also at Mobile World Congress, Internet of Things network operator UnaBiz launched a smart button. The physical button, similar to Amazon.com Inc.’s Dash button, allows consumers to reorder a particular product quickly by pressing a button.