Amazon’s second annual Prime Day may have been the biggest sales day in the company’s history, but it was the fourth-highest traffic day for the company in the past year. Apps could explain why. Inc. generated less traffic to its site on Prime Day 2016 than it did on Prime Day 2015, the first year Amazon held the mid-summer sales event. But that may be because more consumers were accessing Prime Day deals through the highly popular Amazon mobile app.

Data released by online consumer intelligence firm Hitwise, a division of online marketing technology provider Connexity, found that recorded 81.6 million site visits on Prime Day 2016, up 57% from 51.9 million on the previous Tuesday, but down 5.6% from Prime Day 2015, when Amazon recorded 86.4 million site visits.

“The decline in visits to did necessarily not translate to a decline in transactions, however, and could also be a sign that customers are increasingly supplementing their browser sessions with Amazon’s mobile app,” Hitwise writes. Amazon has by far the most popular shopping app, which was installed on 36% of U.S. Android devices in April, far ahead of second-place eBay at 17.5%, according to SimilarWeb, a provider of online data. Comparable data for Apple devices is not publicly available.

Amazon itself emphasized the growing role of its mobile app ln this year’s Prime Day. Amazon said Wednesday orders placed on its mobile app more than doubled year over year compared to Prime Day 2015.

That could explain why while Prime Day 2016 was the biggest sales day in Amazon’s history, according to Amazon, it was only the fourth-busiest day in the past year in terms of traffic to, which does not include app visits. Here are the top five, according to Hitwise:

  • Cyber Monday 2015: 95.3 million visits
  • Black Friday 2015: 87.1 million visits
  • Prime Day 2015: 86.4 million visits
  • Prime Day 2016: 81.6 million visits
  • The Sunday before Cyber Monday 2015: 80.2 million visits

Price monitoring firm 360pi’s analysis found that Amazon offered more than 6,500 Prime deals in the U.S., with an average discount of 26%. By comparison, Amazon offered an average discount of 30.1% on more than 59,000 items between Black Friday and the Sunday before Cyber Monday 2015. 48% of all Prime Day deals were for items sold by Amazon and not its marketplace sellers, which account for the majority of products sold on Amazon.

While the day was a boom for Amazon, it wasn’t nearly as robust for its marketplace sellers, according to new data. ChannelAdvisor Corp., which facilitates sales on online marketplaces such as Amazon, shows that same-store sales for its U.S. marketplace clients—meaning merchants that participated in Prime Day this year and last, fell 3% year over year.

“While Amazon expanded the number of offers [from marketplace sellers] this year, they are still the minority of both the number of deals that are run as well as the transactional volume [gross merchandise volume],” writes ChannelAdvisor executive chairman Scot Wingo.

Amazon, No. 1 in the Internet Retailer 2016 Top 500 Guide, has been making a push into the apparel space in recent years, and that showed on Tuesday.

Data from 360pi illustrates that men’s fashion (6.5%) accounted for the highest percentage of all deals offered, while women’s fashion was the fourth highest at 5.2% of all deals. Electronics accounted for 5.4% of all deals offered, third most among all categories.


Meanwhile, retail and e-commerce pricing analytics firm Boomerang Commerce analyzed more than 100 spotlighted deals and found that 25.9% of those deals were for apparel, the most out of any category and more than 300% higher than the next closest category, which was home goods (7.2%).

Amazon wasn’t the only major retailer offering big deals on the day. In fact, of the 50 largest retailers in North America, an Internet Retailer analysis showed that 23 in addition to Amazon were offering some sort of deal on Prime Day.

While Amazon wasn’t alone in offering deals, the e-commerce goliath offered the lowest prices, according to data from Boomerang Commerce. Boomerang’s finds that Amazon’s prices were 36% lower than those offered by Wal-Mart Stores Inc. (No. 4) and Toys ‘R’ Us Inc. (No. 35), both of which were running promotions to compete with Prime Day, and 29% cheaper than Target Corp..

Jenn Markey, vice president of marketing at 360pi, says running sale to compete with Amazon’s annual event might not be the best strategic move for retailers.

“Amazon is playing its own game and a lot of other retailers, particularly ones that are not necessarily winning, are being sucked in to playing on Amazon’s home field,” she says. “I don’t think that’s a wise decision long term. The more the other retailers talk about it and have their own flash sales, the more they legitimize that Amazon Prime is the place to be on that day and other days.”