Smartphones users want things fast.

In fact, 78% of U.S. consumers say when they research products on their smartphone, they are looking to buy within the day, according to the recently released report “2016 Mobile Path to Purchase” from website traffic measurement firm Millward Brown Digital. The online survey, commissioned by marketing firm xAd Inc., polled 5,048 consumers in March from the United States, the United Kingdom, Germany, China and Japan who researched retail purchases on their smartphone.

Smartphones are a key part of retail, the report finds, although their influence varies by country. At least 30% of global retail shoppers rank their smartphone as the most important device for retail research. In the United States, 31% of consumers rank their smartphone as the most important, while in China, half of consumers rank it as the most important device for retail research.

Among U.S. consumers, 58% say they’ve used their smartphone to research clothing and apparel purchases within the past 30 days, the highest of any retail category. Grocery, however, wasn’t far behind, as 57% of U.S. consumers say they have used their smartphone to research a grocery-related purchase within the past 30 days. In China and Japan, grocery was the most popular retail category, as 88% of Chinese consumers and 63% of Japanese consumers researched grocery information on their smartphones.

More about online grocery sales: It’s a breakout year for online food sales and Internet Retailer’s new report on the online food and beverage market.

The next most popular retail categories for U.S. consumers to research on their smartphone were:

• Electronics, 41%
• Home goods and home improvement, 39%
• Beauty and wellness, 37%
• Games and entertainment, 31%
• Sports and leisure, 23%

Consumers could pick more than one response.

U.S. consumers visited Amazon.com Inc., No. 1 in the Internet Retailer 2016 Top 500 Guide; Wal-Mart Stores Inc. (No. 4); Best Buy Co. Inc. (No. 20); Target Corp. (No. 22); and Kohl’s Corp. (No. 19), most frequently and in that order on their smartphone among retailers, according to the report.

In-store visits remain a key part of retail purchasing, especially in the United States. 67% of U.S. consumers (the highest among the surveyed countries) say they visit a store location to complement their smartphone retail research. xAd recommends marketers to use a smartphone’s location to deliver relevant messages if a consumer is researching a product and is near a store.

Of course, consumers typically have smartphones in their possession while in a physical store: 24% of U.S. consumers say they access retail information on smartphones while in a store, a 75% increase from 2013, when only 6% of consumers said this.

U.S. consumers are on their smartphones even when other devices are nearby. This also holds true for when a consumer is looking at retail products, according to the report. 54% of U.S. consumers say they access retail-related information on a smartphone while at home, which is a 41% increase compared with 2013, when 32% of consumers said they did so.

Retail marketers should use a consumer’s location—whether at home, around town or in store—to make sure advertising is relevant, says Sarah Ohle, senior director, insights and innovations at xAd. “Messaging that enforces branding and provides useful information, such as price comparisons and reviews, works while shoppers are at home,” Ohle says. “Dynamic distance showing the closest retail store is beneficial while [a consumer is] out and about, and action-oriented calls to action, such as coupons and loyalty programs, should be employed while shoppers are at a business location.”