A new report indicates that retailers and brands have a powerful channel to distribute digital coupons and loyalty cards via mobile wallets: wallet users themselves.

Paybefore (Banking Technology‘s sister publication) reports that an analysis of Apple Wallet users by mobile engagement specialist Urban Airship found that every digital coupon or loyalty card a user installed on the wallet was shared to an average of 3.3 other mobile devices.

Overall, more than three-quarters of all retailers’ coupons and loyalty cards installed on Apple Wallet were the result of sharing by customers versus being created and distributed through marketing channels.

Every Apple Wallet coupon and loyalty card features a built-in “share” link, facilitating easy sharing among family and friends. The Urban Airship data indicate consumers are using the sharing feature in droves. Mobile coupons were shared more than loyalty cards, with each coupon shared an average of 4.3 times, versus 2.9 average shares for a loyalty card.

The data also show that sharing is occurring at a peer-to-peer level rather than being facilitated by brands or digital aggregators, as 95% of shares were to seven or fewer devices. Meanwhile, just 1.1% were to 16 or more devices.

“Apple Wallet passes unlock network effects for business growth, lowering the cost of customer acquisition by offering an incredibly simple path for customer referrals and repeat business,” says Brett Caine, CEO and president, Urban Airship. “Best of all, any size business can implement mobile wallet passes, which are 10 to 25 times less expensive than traditional plastic cards and offer dynamic updates and lockscreen notifications for expiration alerts, location-aware reminders, new loyalty levels achieved and much more.”

A previous study by Urban Airship, released in 2016, found that consumers were more likely to use coupons and loyalty programs offered via the mobile channel. Furthermore, coupons and loyalty programs ranked as the top two features consumers most desired in their mobile wallets, the report found.