Google has released an official AdSense app for Android and iOS and it allows AdSense users to keep track of their earnings on the go. You can keep an eye on your latest earnings for the day, see what you earned yesterday, and view your earnings for the month so far — plus lots more.
According to release notes,
The AdSense app provides an easy way to access key data from your AdSense account. Access reporting features anywhere, directly from your iPhone. The first version of the app gives you access to: the key earnings information, top custom and URL channels, ad units and sites reports, payment alerts.
For your information, like AdSense app for Android, the AdSense app for iOS also comes with limited features. AdSense app for iOS is absolutely free and it operates in a smooth & responsive manner.