You are probably aware that you can disable password prompts altogether for free downloads made on your iPhone, iPod touch, iPad and Mac. As an added layer of protection, iOS and macOS will either require your Apple ID password for each paid download or after fifteen minutes of making your last purchases in the iTunes Store, App Store, Books Store or Mac App Store, depending on your preference.
What you cannot do on iOS and macOS is disable password prompts for both free and paid downloads. On the Apple TV, however, it's possible to turn off password protection for both free and paid items and this tutorial will help you do just that.