No one is exactly safe from ad tracking, not even iPhone users. That's despite Apple's promise of "what happens on your iPhone, stays on your iPhone."
Still, there are some ways to somewhat "limit" the user data that advertisers and companies collect on iOS, and doing so is as easy as 1-2-3.
Enable 'Limit Ad Tracking'
As its name suggests, turning this on will put a cap on the info that marketers can get. That way, they can't target users with ads that are based on what they search for online. This doesn't put a stop to ads altogether, though, and they'll probably start seeing unrelated stuff.
Step 1: Go to Settings.
Step 2: Tap on Privacy.
Step 3: Tap on Advertising.
Step 4: Toggle on Limit Ad Tracking.
Turn Off Location-Based Ads
Simply put, these are ads that are based on a user's location, and disabling this will give way to less relevant ads moving forward.
Step 1: Go to Settings.
Step 2: Tap on Privacy.
Step 3: Tap on Location Services.
Step 4: Tap on System Services.
Step 5: Toggle off Location-Based Apple Ads.
Block All Safari Cookies
For those who use the Safari browser on their iPhones, the app's data-collecting activities can be restricted by blocking cookies and preventing cross-site tracking. However, take note that certain features on a website might stop functioning, and other pages may not even work at all.
Step 1: Go to Settings.
Step 2: Tap on Safari.
Step 3: Under Privacy & Security, toggle on Prevent Cross-Site Tracking and Block All Cookies.
Disable Background Refresh
As Apple puts it, Background App Refresh lets apps check if there's a new update or new content available when they're suspended, but apparently it's more invasive than advertised.
Step 1: Go to Settings.
Step 2: Tap on General.
Step 3: Tap on Background App Refresh.
Step 4: Tap on Background App Refresh at the top of the page and set it to Off.
Clear Tracked Data
Just to start off on a clean slate of sorts, there's a way to clear the data that apps and such have collected so far.
Step 1: Go to Settings.
Step 2: Tap on Privacy.
Step 3: Tap on Advertising.
Step 4: Tap on Reset Advertising Identifier and confirm.
Why This Matters
Geoffrey Fowler of The Washington Post recently found out that the apps on his iPhone have been gathering and transmitting data during the night as he slept. For instance, he and the privacy company Disconnect discovered that the aforementioned Background App Refresh feature lets apps collect and relay info even when they're not in use.
This, of course, spells bad news for iPhone users who value their privacy and prefer not to get flooded with targeted ads and the like.