Both the iPhone 5 and iPhone 6 outperformed the iPhone 7 over the Christmas period in 2016, according to AppsFlyer.
The data comes from the firm's recent 2016 Holiday Season Study which looked at sales data and phone activations during the period.
It shows that the iPhone 6 was the most popular phone in the US, making up 36% of all iPhone activations. The iPhone 7 accounted for 33% of activations.
Across the pond
In Western Europe, AppsFlyer found that the iPhone 5 made up 42% of all iPhone activations. The iPhone 7 sold even fewer than in the US, with only a 17% share of activations.
On Android, Samsung was the clear winner in both the US and Western Europe. Samsung devices accounted for 50.5% of activations in Europe and 47.8% in the US.
As for sales and installs on devices, the study found that Black Friday and Cyber Monday were the most popular days for users to make purchases in both regions.
Both sales and installs declined from Cyber Monday to Christmas. However, from Boxing Day, installs rocketed up as new device owners populated their phones with apps.