The darling of retailers this holiday season is the smartphone.
Following years of less-than-stellar sales through mobile devices, phones have now turned into reliable cash machines for online merchants looking to move as many TVs, toys and trinkets as possible during the busy shopping season.
For nearly half of US holiday shopping, phones have become the default device for browsing virtual aisles. And customers this season are buying many millions more dollars' worth of products through those devices, according to Adobe Analytics.
On Cyber Monday, phones accounted for 47 percent of traffic to online stores and 36 percent of sales -- big increases from last year, Adobe said. Total sales through phones on Cyber Monday hit $2.2 billion, up from $1.4 billion a year earlier and hitting a record that was set just days earlier on Black Friday. Black Friday became the first day ever to reach more than $2 billion in online US sales coming from phones.
"It's just becoming easier and easier to buy from a phone," Lynsey Thornton, a vice president for e-commerce software company Shopify, said Monday.
Improvements in mobile shopping are allowing consumers to buy the stuff they want while on the go and often much more quickly than when firing up a laptop or desktop. Retailers are benefiting, too, since their customers already spend nearly as much time on phones as they do watching TV.
"Converting mobile traffic to sales has long been a thorn in the side of retailers, but investments in making the experience faster and easier have paid off," Adobe's Taylor Schreiner said Monday. "Cyber Monday shoppers relied heavily on their mobile devices, resulting in an unprecedented 55.6 percent year-over-year increase from smartphones alone."
On Cyber Monday,, making the day the biggest online sales day in US history, Adobe said. That record isn't a surprise, since it's typically .
Amazon said its Cyber Monday sales were the and Black Friday sales surpassed last year in terms of items ordered, but it didn't provide specific numbers. It said the top-sellers on its site since Thanksgiving have been Amazon's , Fire TV Stick 4K with Alexa voice remote, Fire 7 tablet, Amazon Smart Plug, Instant Pot and 23andMe DNA test.
Cyber Monday's strength continues what's expected to be the strongest holiday shopping season in years. For Black Friday, US online sales hit $6.22 billion, up from $5.03 billion last year. Purchases via phones reached $2.1 billion, crushing the previous record of $1.4 billion last Cyber Monday. Thanksgiving weekend also hit a new online sales record, at $6.4 billion.
Since the start of November, $50.6 billion has been spent online, up 20 percent from last year, Adobe said early Monday.
Mobile shopping has been growing all year, but it's still unclear if it will ever overtake desktop as the leading way Americans buy. For this holiday season, Adobe predicted phones would generate 27 percent of revenue, a solid 12 percent improvement from last year but still well below the 63 percent of sales desktop will net.
"I think we're going to continue to see mobile rise," Shopify's Thornton said, "as people become more comfortable purchasing on mobile."
First published on Nov. 26 at 12:39 p.m. PT
Updated Nov. 27 at 8:01 a.m. PT: Adds updated Adobe numbers on Cyber Monday sales.
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