This app used to let you listen to your favorite stations without an account until about 2-3 years ago. The final straw for me was when this app tried to sell me things from a locked screen with my touch ID. A better alternative is to use VLC and open a network stream to your favorite station bypassing iheartradio and its intrusive ads. google iheartradio xml station list for your favorite stations streaming url. Then copy and paste that url into vlcs network stream option.
Nickpfluge about iHeart: #1 for Radio, Podcasts, v8.1.1