How to block ad tracking on your iPhone

In 2019, an article in THE Washington Post by Geoffrey Fowler described the author’s shock when he found out how many of his iPhone apps were collecting and sending information about his use while he slept.

As we all know now, data is a big commodity these days. If you use a phone, laptop or any type of computing device (unless you are a security expert or a cutting-edge hacker with access to sophisticated blocking tools), you are paying for your applications by contributing marketing and other information for the companies that provide them.

As Fowler’s article demonstrated, iPhone users are not immune to this. Since his article was published, Apple has made some commendable changes to its privacy policies. But it’s still a good idea to take control of your own data. There are a few simple ways to minimize the amount of tracking that application vendors can do and the amount of data they can access.

Disable personalized and location-based ads

According to Apple’s advertising and privacy page:

The Apple advertising platform does not track you, which means that it does not link user or device data collected from our applications to user or device data collected from third parties for targeted advertising or advertising measurement purposes, and does not share data from user or device with data brokers.

However, the page continues to inform you that contextual data, such as information about your device, your location, your searches on the App Store, and what you read on Apple News, can be collected. You can work around this by disabling personalized, location-based ads.

To turn off personalized ads

• Select the “Settings” application, tap “Privacy”, scroll down and select “Apple Advertising” (it will be near the end of the list).
• Disable “Custom ads”.

To turn off location-based ads

• Select “Settings”> “Privacy”> “Location services” (at the top of the screen).
• Disable “Location services”.

On this page, you can also change several of your apps, such as the App Store or Maps, to allow access to the location never, ask next time or while using the app. Also, note that you can still use the “Find My Phone” feature; it will temporarily turn on Location Services.

If you want to see how effectively your phone is protected, you can try taking the Panopticlick test, which is offered by the Electronic Frontier Foundation. It monitors the device’s fingerprint, among other things. I ran it on an Apple iPhone 11 after following the instructions above and got a “partial protection” result to block tracking ads, block invisible trackers and protect against fingerprints.

Lock Safari

If you use the Safari browser on the iPhone, there are several things you can do to make it more secure.

• Go to the settings. “
• Select “Safari” and scroll down to the “Privacy and security” section.
• Enable “Prevent Cross-Site Tracking” (which means that advertisers and other third-party content providers cannot track you from one site to another).
• Activate “Block all cookies”. Cookies collected by various websites can contain a large amount of information about how you use the website, what information you place on it, etc. By blocking cookies, you prevent data from being collected.

However, you will probably make things very inconvenient for yourself. Your visits to websites will not be recorded, so, for example, you will not be able to revisit a playlist or repurchase the same shirt you bought last year. Some sites even refuse entry if you do not allow them to collect cookies. It is your choice.

Disable background application update

According to Apple, the reason for enabling application updates in the background is to allow suspended applications (applications that are not currently active) “to check for updates and new content.” According to Disconnect, the privacy app company Geoffrey Fowler cites in his article, it also allows apps to collect marketable tracking data and transmit that data even when you’re not using the app. Interestingly, iPhones ship with Background Application Update enabled, but it’s not too difficult to turn it off.

• Go to the settings. “
• Select “General”.
• Select “Background application update”.
• You will see a list of all applications that use this feature and they will all be activated. Find “App update in the background” at the top of the page and touch it.
• You will be taken to a page that allows you to enable it for cellular and Wi-Fi data, only for Wi-Fi, or you can turn it off completely. Select “Off”.
• If you go back to the previous page, you will see that all toggle buttons for the various applications have disappeared completely.

You may want to be selective about which applications can run in the background. Some applications may not work well in another way. For example, Google Photos will not automatically back up the camera roll unless this feature is enabled. Therefore, you can, if you wish, leave “Background application update” enabled and then choose which specific applications you want to disable.

Update of March 8, 2021, 17:00 ET: This article was originally published on May 30, 2018; several parts have been updated to reflect changes in iOS.