According to new data out of App Annie, consumer spend on Android applications is set to overtake that of users on iOS platforms for the first time in 2017.

However, according to the breakdown of the data, this feat will come with a catch.

App Annie say that Apple’s iOS platform is on-track to bring in $40 billion in 2017 while the Google Play Store is estimated to account for only $20 million.

Despite the Google Play store only bringing in half of Apple’s take, the firm says that transactions through Amazon, Samsung, and SlideMe’s own app platforms will push the platform ahead of iOS by roughly $1 billion ($41 billion in total).

While this bump will put Android as a platform ahead for the first time, it’ll prove an obstacle for Google in the long-run.

App Annie say that by 2021, Google will be making about $42 billion a year on the Play Store but still trail Apple without assistance from third-parties.