Every PDF, single chart or playlist booklet, carries a small Made in iReal Pro credit at the foot of each page, and there is no setting to remove it.

 

It acknowledges where the chart came from and helps support the app. If you must remove it, you can delete or cover the text in a PDF editor or vector app, outside iReal Pro.

 

For more, see Print a chart or save it as a PDF on the iReal Pro website.