Posted with permission from Popular Science

Prevent Google and Apple from tracking you

You've beefed up the security for your online accounts, so you feel confident sticking your smartphone in your pocket and heading out the door. But many consumers don't realize that the software in their phones can track their every move. Whether you have an iOS or an Android device, Apple and Google can collect data about how you use it: the places you go, the apps you run, the search queries you type into the web browser, and so on. You can read detailed privacy policies for both Apple and Google online.

Although this sounds unnecessarily invasive, the companies use a lot of your data in helpful ways. For example, Apple relies on crash reports from apps to fix bugs in its software,while Google keeps tabs on your location so it can tell you how long the drive home will be. Are you comfortable with your phone reporting its location if it means you can find it when it gets lost? If your desire for privacy outweighs these benefits, you can decide how much you trust these companies with your data and how much information you're prepared to share with them. Whatever you choose, it's important to be aware of what you're sharing, and how you can limit it if you want to.

Privacy on iOS versus Android

Apple Privacy Policy
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Apple Privacy Policy
Apple also publishes its privacy policy online.

Apple tends to limit its data collection, from email scanning to location tracking, to fewer locations than Google does. A lot of personalized data, like the stuff Siri knows about you, stays locked on your device and never goes back to Apple's servers. Apple also keeps less personal information on its users. Additionally, as its executives have pointed out, Apple's data is more anonymized than Google's, allowing the company to learn about the habits of its users without storing complete profiles on those individuals themselves.

Google would say that the extra data it collects, from what you've watched on YouTube to your home address, helps customize its services and apps for users, with better personalization and programs that recognize you across all devices. We'll let you decide on that.

No matter which system you use, your phone's privacy settings will allow you to specify the data Apple or Google can collect about your behavior. Here's how to pick and choose which information you're willing to share—or not.

Privacy settings on Apple's iOS

On an iPhone, the Privacy menu in Settings is the obvious place to start. Tap Location Services then System Services to change how your location can be used by Apple and how it can't. Turn off the Location-Based Apple Ads switch, for example, and you won't receive ads based on where in the world you currently are.

Tap Frequent Locations, meanwhile, and you can prevent iOS from keeping records of places you normally visit, information that's used to provide location-related features in Calendar, Maps, and other Apple apps. As well as disabling the feature, you can wipe the location history that your iPhone has built up.

The location-use menu includes dozens of switches, from My Find iPhone to Routing & Traffic. It's your call which ones you're comfortable enabling. You can also switch location monitoring on or off for individual apps, Apple-made or third-party, from the main Location Services menu.

Frequent locations
David Nield/Popular Science
Frequent locations
Several Apple apps use data on your favorite places, but you can erase it if you want to.

In addition to your location, Apple gathers information on your phone's hardware and software performance. Head back to the Privacy screen, tap Analytics, and you can control how much of this anonymized data Apple sends back to base and to developers.

You can also control whether Apple will use your information in order to try to serve up more relevant advertisements. Tap Advertising then Limit Ad Tracking to turn off personalized ads on iOS, or Reset Advertising Identifier to wipe all the data that's been collected so far.

Limit Ad Tracking
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Limit Ad Tracking
You can limit the data Apple uses to target you with ads.

All of these settings come with explanatory notes you can read through if you want to know more about why the data is collected and how it's used. It's worth reading up on the issues to help you strike a balance between privacy and convenience. Remember that stopping ad tracking won't necessarily reduce the number of ads you see, but it will increase the chances that they won't interest you.

Outside of the Privacy menu in Settings, you can customize apps individually. To clear everything that Siri knows about you, for instance, you have to switch off both Siri itself (via Siri in Settings) and dictation (via Keyboard under General in Settings). If you open the Safari menu in Settings, you can turn off suggestions based on sites you've visited in the past, and stop Safari from showing frequently visited sites as well.

Siri
David Nield/Popular Science
Siri
The only way to delete Siri's data is to switch it off and do without it.

Remember that a lot of apps and websites will be collecting data on you even if Apple isn't, and you're going to need to configure these app settings separately. That includes apps from Google, if you have installed them. Open up Google Maps for iOS, tap Settings, and you can prevent Google from tracking where your iPhone is going (the Personal content menu) and the places you've been to in Maps (the Maps history menu).

Much of what you do on your iPhone, like your iMessage history, isn't monitored or tracked by Apple. Apple is also less interested than Google in building up a profile of you for its advertisers. So, as far as privacy on iOS goes, you should focus on locations and past searches. Just be aware that, if you stop this data from being tracked, you won't get the convenient features that go along with the monitoring.

Privacy settings on Google's Android

As we mentioned earlier, compared with Apple, Google's apps typically collect more data about you across more platforms. To be fair, Google also gives you an intuitive and straightforward interface for managing all this data.

Open up the Settings app in Android, tap Location, and you can set whether or not your Android device knows where you are at all times, as well as control which apps have access to that information. Another option on the same menu, Google Location History, lets you stop location data from being sent back to Google (so that it will be synced across all your devices and the web).

Location
David Nield/Popular Science
Location
You can easily switch off location tracking for your Android phone.

To manage the data logged by Android and other Google services, choose Google from the Settings app, then Personal info & privacy. You can either work through the Privacy Checkup offered by Google, or configure the different types of activity manually: location tracking, web search logging, voice commands you've used on Android, and more.

Tap Activity controls, and you can view and delete information in seven categories, and stop this information from being logged in the future. To clear your "OK Google" voice searches, for example, choose Voice & Audio Activity, then Manage Activity. Turn the tracking off, and no future voice searches will be saved. The other activity sections, including location and web searches, work in the same way.

David Nield/Popular Science
Voice & Video Activity
Google lets you wipe the data it's collected at any time.

As with Apple's services, you need to decide where you want to draw the line. Tracking what you've looked for on the web and asked Google about in the past will help the search engine serve up more relevant answers in the future (or at least that's Google's promise). Google follows Apple in giving you lots of background information about each option and each type of data as you work your way through the menu.

Further down the Personal Info & privacy screen is an option for Ads Settings. If you tap on this, you can choose whether the ads you see are personalized to you, and even give Google some clues about the topics you're interested in, based on everything you've done with Google apps and Android in the past.

Snapchat permissions
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Snapchat permissions
You can also set which permissions individual apps have.

Remember that Google collects data from plenty of sources, including Android TV boxes and the Google Home speaker you might have set up in the living room. If you want to manage the data collected from all these places, head to your Google account page on the web.

As on Apple devices, it's a good idea to check on what individual apps are logging about you, outside of Google's own software. You can do this via each app's respective privacy policies. If you see something you're not comfortable with, uninstall the app in question, or modify its permissions via the Apps menu in Settings.