You can't possibly pretend to understand the laws from every single country. That is the reason why you need a lawyer. This app targets all countries in the world. Even if it was just for the US, you would need one.

Well, obviously, I can't even read the codes of other countries! Even if I could, I wouldn't trust myself to understand them - cultural context matters for understanding. Like, how much "must" is there in "should" and similar. I'm asking more about your local laws (so, state + federal, in the US?) - obviously, if you need to cover multiple jurisdictions, that's a pain better outsourced to specialists.