One day I was in a restaurant with a friend. My friend was later shown an ad on her phone related to the topic of our discussion. Did you know that apps on our phones can listen in and serve up ads accordingly? These are called triggers. When your phone picks up on certain phrases (triggers), apps on your phone can serve up related ads.

Many people don’t understand just how much info our phones are collecting. And while we may be concerned about the invasion of our privacy, we often unknowingly permit apps to collect our info. I’ll outline how much and what type of info our phones are collecting and what we can do about it.

First, What Apps Collect Information

Our phones may collect the following information about us, depending on our phone and app settings, including privacy and permissions and the apps installed on the phone:

• Contact info: Name, email, phone number, address, and your friends’ contact info
• Health and fitness: Age, medical data, fitness, and exercise data (e.g., Apple Watch, Apple Health)
• Financial info: Banking data, purchase history, credit score, salary and income, debt (e.g., online banking app with credit score checking, Amazon purchases)
• Location: Precise location (e.g., apps like Apple Maps, Google Maps, or Waze that use location services to navigate or find services)
• Sensitive info (from social media or family history apps): Race, religious beliefs, political opinions, and genetic information (e.g., DNA apps such as 23andMe)
• User content: Emails, text messages, photos and videos, and audio from your phone’s microphone
• Browsing and search history: Clicks, scrolling, music listening, video views, and app usage

Why Do Apps Collect Our Info?

Free apps such as Google, Twitter, Instagram, Facebook, and many others make money through advertising and selling user info to companies interested in patterns of behavior. That information later helps shape marketing campaigns.

For example, if people are searching for baby-related products for grandchildren, marketers want to know which products are of interest and for what demographic groups. Young adults might be shopping for diapers while grandparents could be looking for games they can play with a toddler. If you’re in the grandparent demographic profile, you are contributing to the profile of what grandparents might buy. Companies use this info to shape product development and to hone their marketing campaigns.

Second, the Pros and Cons of Tracking

Generally, most of us don’t like the idea of apps tracking and gathering info on us. However, some tracking can be useful and can provide us with critical information:

Pros

Advantages range from helping to keep us well, keeping us safe, finding our lost device, or protecting us from travel challenges:

• Health and fitness: Apps can accurately track our steps, distance, heart rate, sleep, and more. By keeping track of this info, apps can motivate us to meet our daily exercise goals.
• Fall detection: Some smartwatches can detect if you (or a loved one) fall and contact a designated person or emergency service for help
• Find nearby stores or restaurants: Based on tracking your location, your phone can help you find nearby stores or restaurants, e.g., “pizza shop near me” or “lowest gas prices near me”
• Driving directions: With location tracking, apps can get us to our destinations faster by analyzing traffic patterns and finding the fastest routes or warning of construction delays ahead. Some driving apps can help you avoid getting a traffic ticket by letting you know police are ahead. Finding a lost device: Tracking can help you locate a lost phone, watch, or other devices—or even remind you that you left your phone in the car.
• Weather info: Weather tracking can help us shape our outdoor activities—with daily or hourly forecasts based on your location or by entering the location of where we are headed. Weather apps can also warn us if severe weather is headed our way, enabling us to seek shelter in time.

Cons

Companies are making money by tracking you—and it can be disturbing when we realize how pervasive it is. Even more, we likely opted into it by agreeing to terms and conditions and by enabling useful features on our devices. Below are a few negatives of tracking:

• It feels like an invasion of our personal space: It’s annoying knowing that companies can snoop on our daily habits and profit from them. Whether it’s showing targeted ads based on our online activity, or secretive tracking based on conversations, it can make us feel helpless if we don’t know how to stop it.
• Loss of privacy: Ads can seem creepy and disturbing when we realize that some apps know where we’re at all the time or when we know that some are listening
• Tracking info could fall into the wrong hands: With increased tracking info being collected, sold, and used by advertisers, the potential for it to be obtained by identity thieves also increases¹
• Even if you disable tracking, some companies still track you: In recent years, news reports revealed that we may still be tracked even if we’ve turned location tracking off.²

Third, What Can We Do to Prevent or Appropriately Enable Tracking?

Many people have accepted tracking because it’s too hard to figure out how to stop it or customize it for specific purposes. But it’s possible to limit or stop tracking and take control of what information is shared, enable sharing location with selected individuals, and even do so by individual apps.

• Turn off location tracking: On iPhones, see Figure 1, go to Privacy, Location Services. Here, at the top, you can turn off Location Services for all apps. However, choosing this option would stop tracking for apps where you find tracking useful. Android location tracking settings are shown in Figure 2.
• Choose location tracking options for each app: On iPhones, in the Location Services section, you can choose location options for each app. Options include, Never, Ask Next Time or When I Share, While Using the App, and Always. For driving direction apps, I chose While Using the App because they need my location to give me directions. Android devices have similar settings. 
• Disable setting that lets advertisers track you: Google search for Digital Trends “How to control your location on iOS and Android” to learn how to turn off the option that lets advertisers send you ads based on your location.
• Share your location setting: On iPhones and Android devices, you can share your location with family and friends. Wired Magazine’s article “How to Share Your Location on an iPhone or Android” provides instructions on setting this option.
• Review “significant locations” setting: On an iPhone, go to Privacy, Location Services, System Services. Near the bottom, you’ll see ‘Significant Locations.” Here, you’ll see the places you have been to most frequently. I found it surprising that my phone knew I had been to Panera Bread just yesterday. This can be switched off, as I just did. For Android users, the Digital Trends article mentioned above provides instructions for setting options to control location history.
• Review checklists for other privacy settings, e.g., microphone, email, and photos: There are lots of other privacy settings on your phone. Going into each of these is beyond the scope of this article. But it can be helpful to check out the checklist of privacy settings, such as PC Magazine’s “10 Privacy Features iOS 15 and iPadOS 15 Users Need to Know.” For Android users, check out The New York Times Wirecutter article, “10 Practical Privacy Tips for Your Android Phone.”
• Consider using non-tracking search engines and browsers
  If the tracking aspects of search engines and browsers are worrisome, consider newer non-tracking search tools like DuckDuckGo or non-tracking browsers like Brave.

To Summarize

First, your phone’s likely tracking and sharing more info about you than you realize. Your info is sold to advertisers to help them advertise better. Second, not all tracking is bad—there are pros and cons. Third, you can limit or stop much tracking on your phone. But turning off tracking settings aren’t full proof. Even with tracking settings turned off, you still may be tracked.

Advertisers Won’t Be Listening in While I’m Dining Out

Following my restaurant listening experience, I reviewed the microphone privacy settings on my iPhone and disabled most apps that had access to my microphone. It takes a bit of work to learn about the privacy settings on your phone, but I think it’s worth it. I feel better knowing that I turned on tracking settings that are useful to me and turned off the settings that seem valuable to advertisers.