If you want to provide feedback on whether you like a track by rating it you can thumbup or thumbdown the currently playing song.

There are three ways to thumbup or thumbdown music
  1. While in the app you must do it from the fullscreen player. To get to the fullscreen player drag the mini-player with the track name and artist name up, or simply tap on it.
  2. Using the notification player you can thumbup or thumbdown songs. You can access the notification player by dragging down the notification player while music is playing in iHeartRadio.
  3. Using the lockscreen player you can thumbup or thumbdown songs. You can access the lockscreen player when your device is locked and displaying all notification content is enabled in your Android settings.
Not seeing the lockscreen or notification player? Make sure you haven't disabled notifications for iHeartRadio in Android Settings for the notification player or disabled notification details in your lockscreen settings.