Rules on using the public API?

My application only uses two resources ( and

These don’t require any kind of authentication to access.

I’m wondering, if I want to distribute an app using these resources, do I need to sign up as a developer and provide a key? Also, am I allowed to monetize such an app with my own ads or by charging for access? Thanks.

I read that, but it doesn’t answer my questions. The page says that only certain features require a developer account, but I’m using publicly available data that doesn’t require a user to log in. I don’t know what the restrictions are in this case.

I don’t really see anything about application monetization on this page. I assume since it’s not explicitly prohibited, it’s safe so long as I follow the ToS, but I want to be 100% sure before I do so.

monetization is allowed “provided they don’t disable our ads and comply with our API rules”