Google's Android powers 86% of smartphones worldwide, according to IDC, while Apple's (AAPL 0.51%) iOS controls the remaining 14%. Therefore, it wasn't surprising when Sensor Tower reported that the Alphabet (GOOG 1.43%) (GOOGL 1.42%) subsidiary's Google Play store logged 20.7 billion downloads in the first quarter of 2019, versus 7.4 billion downloads for Apple's App Store. But there's a twist: The App Store generated significantly more revenue than Google Play, despite having fewer users.

Chart showing Google Play vs. App Store revenue in Q1 2018 and Q1 2019

Data source: Sensor Tower. Chart by author.

This trend isn't new. Last year, App Annie reported that Android users accounted for 70% of all app downloads in 2017 but just 34% of app consumer spending. Apple users accounted for 30% of downloads but 66% of spending.

Analysts attribute the split to several factors: iPhone users are generally more affluent than Android users, so they buy more apps; many Android users in developing countries lack credit cards; and the Android ecosystem is fragmented, with older hardware that can't run newer apps.

Google and Apple both retain a 15%-30% cut of their app store sales. Since Apple's platform offers easier monetization than Google's, developers may prefer to launch their apps on iOS before Android -- which would give Apple an edge against Google.