Does this sentence from the documentation imply that I can get public data from the api without using OAuth?
"By default, your application can only access the user's public data. If your application needs to read more private data or change associated data, your application can request a larger permission scope through the authorization flow."
There are several API-methods for which you don't need to authorize. Have a look at the API-documentation - for every API-method it is stated whether or not the call needs preceding authorization.