The Settings app on iOS is a miasma of important and obscure settings. With dozens of lines on the main screen, then more settings when you tap one of the main headers, it can be difficult to find where specific settings are hiding.
With iOS 9, Apple made it possible to search the Settings app, but I’ve found that most people don’t know this. In fact, I was just chatting with a knowledgeable friend who had forgotten this search was possible. So, it’s worth reminding users that when you’re looking for a setting, you can search for it, if you know what it’s called.
When you open the Settings app, it looks like what you see at the left. See the Search field? Of course not; it’s hidden. Drag the window down a bit, and you’ll see it:
Type something into the Search field, and you’ll see the results; just tap one to view it. You don’t need full words; the search results work like a Spotlight search, which gives you results as you type.