Apple’s 2021 privacy updates have advertisers approaching iOS with caution and accelerating their investment in Android. Last May, soon after the changes rolled out, US Meta ad spending rose at about the same pace on both types of devices. By the end of December, growth on iOS had slowed to 3% year over year, while Android’s soared to 101%.

In interviews, mobile advertising leaders reported that some mobile advertising may have shifted to the web as a result of Apple’s rollout of AppTrackingTransparency (ATT) in iOS 14.5. Despite that, we still expect the in-app share of mobile advertising to continue to grow.