The only security and privacy settings for apps are what the operating system offers. Because you are voluntarily installing the app there's a certain amount of assumed trust. Many apps abuse that trust and do things the user never really agreed to. Especially around tracking. Browsers also have to comply with the opening system security, but because the websites you visited are rarely fully trusted they tend to guard privacy and security better. And many people use browser extensions to enhance their security.

Before I learned about the atrocious privacy invasion that came with installing apps, I used to use...Facebook (I know, I KNOW). Then I looked at the privacy notices in the iOS setting for that app. I was flabbergasted. They data mine everything when you install the app. Facebook is easily the most egregious example I’ve ever seen personally, but since then I only use browsers, unless there is no alternative, or it’s for connecting to an institution that already has most or all of that personal info.