Why turn it into an app though? This kind of learning materials is something that can be done in a construction of a website which is more accessible for everyone as an app would just simply make them download and as well clear/allocate some memory for your app. Is this just because of ads or is this a school project of yours? Well if it is a school project I don't think it would be impressive for you or your professors having an app that's only use is to be clickable and has reading materials on it. If it is for ad purposes I think you can still earn on ads and applying it into a website which I think is the best route to go for this kinds of content.