From your smartphone to your laptop to your tablet, your devices are tracking — and reporting — your location in more ways than one. Here’s a rundown of some of the most common ways that your location is being tracked and used by tech companies.

GPS vs IP

There are two ways that devices figure out your location: Via GPS or IP address. GPS stands for “global positioning system.” It’s a system of 24 satellites orbiting Earth that send signals back to GPS receivers. Those receivers use the signals to calculate an exact position. Most smartphones have GPS receivers and, if they don’t, they use other geolocation services instead. Because it’s so common and well-known, GPS is commonly used as the shorthand for geolocation services.

Your IP address is another way that your device can reveal your location. IP is part of TCP/IP, which stands for Transmission Control Protocol/Internet Protocol. It’s basically your device’s address on the internet. When you type a web address into your browser, using letters, your computer reaches out to a Domain Name Service (DNS), which translates it into an IP address, in numbers, that your computer can read.

The geolocation information revealed by a GPS is much more precise and accurate than the geolocation information revealed by your IP address. IP addresses can show your town, state, and Internet Service Provider (ISP), but not much outside of that. GPS, on the other hand, can pinpoint your exact location.

What is location permission?

Many mobile apps — and, increasingly, browser-based websites — ask for location permission. That means they’re asking to have the ability to check on your location whenever they want to. Some apps — like maps, weather, location-based dating, and some social media sites — need that information in order to function properly. But others don’t.

So why would they ask for location permission if it’s not essential to their service? Oftentimes, it’s data that they can sell to advertisers. Remember, nothing is really “free” on the internet, and that goes for apps that you don’t pay money for, too. You’re just paying with your personal information instead of with cash.

Can a VPN hide your location in a location-based app?

Some people use a Virtual Private Network (VPN) to mask their location. However, a VPN works by giving you a new IP address. If you’ve given a location-based service like Maps location permission, they’re using GPS to figure out where you are — not your IP address. That means your VPN cannot mask your location in a location-based app.

It also means that any app that’s using GPS instead of IP to track your location can still figure out where you are. In order to prevent that from happening, you have to go and turn off the location permission in your device’s settings. However, some apps — like ride sharing or maps, for example — won’t work unless they have access to your location. If you choose to revoke location permission, you’ll have to go back in and re-give permission every time you want to use the app.

What is geotagging?

Geotags are electronic tags that identify the physical location of a piece of digital data. In more common terms, it’s a tag that’s placed on a photo, video, or social media post (to name just three things that use them) that identifies where that photo, video, or social media post was created in the physical world. Anyone can read a geotag on a photo using technology that’s available on basically every operating system.

How do view a geotag?

In order to view a geotag on a Mac, all you have to do is open the Preview app, pull down “Tools,” click “Show Inspector,” and then choose “GPS.” If you want a visualization of the location, click “Show in Maps” and see on a map exactly where a photo was taken. If all you want is latitude and longitude, right click the image and select “Get Info”.

In order to view a geotag in Windows, right click an image, click “Properties”, and then click “Details”. This will reveal the latitude and longitude of where the photo was taken.

How do you remove geotags?

You can remove geotags that have already been placed on photos and also prevent your devices from adding them in the future.

First, let’s look at how to prevent future geotags.

For Android:

1. Open the Camera app.
2. Tap on “location tags” or “geotags”.
3. Toggle to “Off”.

For Windows:

1. Right click the photo file.
2. Select “Properties”.
3. Under the “Details” panel, select “Remove Properties and Personal Information”.

For iPhone

1. Tap on the “Settings” icon on your home screen.
2. Tap on “Privacy”.
3. Tap on “Location Services”.
4. Scroll down to “Camera” and change from “While Using the App” to “Never".

And here’s how to remove current geotags on desktop:

For Mac:

1. Open the photo in Preview.
2. Select “Tools” from the menu bar.
3. Select “Show Inspector”.
4. Click on the “i” in the menu bar.
5. Select “GPS”"
6. Select “Remove Location Info”.

For Windows:

1. Right click the file.
2. Select “Properties”.
3. Click “Remove Properties and Personal Information”.
4. Choose to remove the location or all of the file’s metadata.