The article quotes the paper, which says “… learning things that are likely to improve your performance at school (e.g., reading; developing knowledge and skill

The article quotes the paper, which says “… learning things that are likely to improve your performance at school (e.g., reading; developing knowledge and skills in math, science, or the arts), on the job (e.g., updating your knowledge of content and standards in your profession), or in activities that are other-wise enjoyable.” Using an app to learn a new language, extend your vocabulary, or learning new arithmetic tricks would seem to fall into this category. If the Elevate app actually does any of these, then I'd call it "learning" instead of "brain training".