The settings you need to change on your smartphone to stop tracking

Your phone knows where you are, what you do, and roughly what you are interested in, and it shares a good deal of that with companies you have never heard of. Most of it can be turned off in about twenty minutes.

I am not going to tell you to throw the phone in a river. I use one. Here is what actually moves the needle.

The advertising identifier

Every phone carries an advertising identifier, a code that lets companies link your activity across apps.

On iPhone, App Tracking Transparency means apps must ask before tracking you across other apps and websites. In settings under privacy there is a switch to refuse all of those requests at once. Turn it on.

On Android, in settings under privacy and ads, you can delete the advertising ID entirely. Do that rather than just resetting it.

This is the single most effective thing on the list and it takes one minute.

Location

Go through your apps one at a time and set location to while using the app, or never.

Almost nothing needs your location always. Navigation needs it while using. A weather app needs it while using. A game does not need it at all.

Turn off precise location for anything that does not genuinely need it. A weather app works perfectly well knowing roughly which town you are in.

Then find location history. On Android this lives in your Google account activity settings and on iPhone under significant locations, which is buried deep in system services. Look at it once. Most people find the contents startling. Turn it off and delete what is there.

Microphone and camera

Check which apps have permission and revoke anything that has no business with it.

Both platforms now show an indicator when the microphone or camera is active, which is worth watching for.

The persistent myth is that phones listen to conversations to serve advertisements. The evidence for that is thin, and the reason ads feel uncanny is usually simpler: your location, your searches, the people near you, and the sites you visited are enough on their own. That is not reassuring exactly, but it is what is actually happening.

Wireless scanning

Both platforms scan for nearby Wi-Fi networks and Bluetooth devices even when those radios appear to be off, for location accuracy.

This is used for location tracking in retail environments. There is a setting to disable scanning on Android under location services, and turning Bluetooth genuinely off rather than through the control panel shortcut helps on both.

The browser

Use one that blocks third party cookies and cross site trackers by default. All the mainstream ones now offer this and it is not always on.

Turn on whatever the tracking prevention feature is called, set it to strict, and accept that a small number of sites will misbehave.

Consider a private search engine for at least some of your searching.

App by app

Go through your installed apps and delete the ones you do not use. Every installed app is a collection point, running services in the background whether you open it or not.

This is the least technical item on the list and it is more effective than most of the settings.

Two things worth knowing

You cannot turn off carrier level location. Your mobile operator knows which tower you are connected to and that is how the network functions. Settings on the phone do not affect it.

And the operating system itself collects diagnostic data. You can reduce it in the settings, usually under analytics or usage data, and you cannot eliminate it.

What I would do in twenty minutes

Turn off the advertising identifier. Set every app's location permission to while using or never. Disable and clear location history. Revoke microphone access from anything that does not need it. Delete unused apps. Set the browser to strict tracking prevention.

That handles the large majority of it, and everything beyond that is a steeply diminishing return.