Google has announced they are going to discontinue supporting its native iOS and Android apps for AdSense publishers. You will no longer be able to check your earnings and performance using the native apps.
Google said "we will be focusing our investment on the AdSense mobile web interface and sunsetting the current iOS and Android apps." Google added "The AdSense Android and iOS apps will be deprecated in the coming months, and will be discontinued and removed from the app stores by the end of 2019."
The iOS app launched in 2013 and they have continued to support it since but no more. You can download the iOS version and Android version for now until Google takes it down.
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