You may not realize it, but the apps on your phone are constantly collecting data. Some of this data is necessary for the app to function properly. For example, your GPS app needs to know your location in order to give you accurate directions.
But other data that apps collect might be less obvious, and even a bit concerning. So what exactly can apps see, and what can they do with the information they collect? Let's take a look.
Can apps collect data from other apps?
Apps can collect data from other apps but it is usually not the case. The main factors are how good the app with the data has been coded and how bold the apps interested in the data is.
When an app is storing data on your phone locally and also is doing so in an unencrypted way other apps on your phone can collect this data when having permission to access the directories in question.
If the app with the data is not storing it directly on the phone but on their servers (which is usually the case) the other app would either need to access the servers, which is not a thing or it would need to intercept the data being sent to the servers. As most data is sent via an encrypted connection (typically TLS 1.2 or TLS 1.3) there is virtually no risk.
How can apps collect data from other apps?
There are a few different ways that apps can collect data from other apps on your phone.
One possibility is the so-called "data mining". Data mining means that an app scans your phone and collects data that it then sends back to the app developer. This data can include things like your location, the contents of your text messages, or even information about other apps you have installed on your device (like the locally stored data mentioned above).
Another way apps can collect data from other apps is called "screen scraping". Screen scraping means that an app takes a screenshot of another app on your phone and then sends that screenshot back to the app developer. This can happen even if you don't use the app taking the screenshots. This is the biggest threat, but it is usually mitigated because apps with sensitive data (e.g. your banking app) usually have measures in place to suppress screenshots and screen videos.
All right, now you know. If you want to learn more about the basic workings of how apps can collect in the first place, I invite you to stick around. I'll go into more detail for you:
Why apps can collect data
See your phone's operating system is designed to suppress certain sections of your phone's memory from other apps. But an app can request access. This is what results in the pop-ups were your phone is asking you if you want to grant access for xyz for a specific app. Let's be honest: we often carelessly confirm. This results in the app being able to see some of your other app's data.
In many cases granting permission to an app is perfectly fine.
For example, a map app can request access to your phone's contacts in order to find your friends' addresses and show them on the map. Or, a social media app might request access to your camera in order to allow you to take and share photos.
However, often apps state in their terms of use that the data will not be used exclusively for the obvious (and usually necessary) way to ensure the app's proper function. Those "other" use cases of your data are commonly the following:
- To create a user profile to sava data
- For behavioral advertising
- To sell your data to other companies
So, even if an app doesn't need access to your list of contacts, it might still request it in order to collect that data and sell it to other companies. And you would have no way of knowing because the app's terms of use would likely allow for that type of data collection.
How apps are bypassing restrictions
Some Android apps are able to bypass these restrictions by using a technique called "side-loading."
Never heard of it?Side-loading is when an app is installed onto a phone through unofficial channels, such as third-party websites or app stores. Once these apps are installed, they can access data from any other app on the phone, without the user's knowledge or consent.
These apps are often designed to look like legitimate, well-known apps, but they may be loaded with malware or may be designed to collect your data and sell it to third parties.
Note: Usually you don't have to worry about side-loading when using a major app platform like Google's Play Store or Apple's App Store as they review apps before adding them to their library.
What Data Do Apps Collect?
There are two main types of data that apps collect: personal data and usage data. Personal data is any information that can be used to identify you as an individual.
This includes things like your name, address, and date of birth. Usage data, on the other hand, is information about how you use the app. This can include things like the amount of time you spend using the app, which features you use most often, and so on.
Most apps will collect both types of data, but there are some that only collect one or the other. Here are two examples:
On one hand, a weather app only needs to know your location in order to give you accurate forecast information, so it will only collect usage data.
On the other hand, a social media app like Facebook needs to know quite a bit about you in order to show you relevant content, so it will Collect both personal and usage data.
What Do Apps Do With This Data?
Generally speaking, there are three main things that developers do with the data they collect: they use it to improve their services, they sell it to third parties, or they use it for marketing purposes. Let's take a look at each of these in turn.
Using Data to Improve Services: Many developers collect data in order to improve their apps. For example, Google Maps collects usage data in order to learn which routes are most popular so that they can provide better directions. Similarly, Netflix uses data about what shows you watch and when you watch them in order to make better recommendations about what you might want to watch next.
While this type of data collection is generally harmless, it's important to remember that companies will rarely be completely transparent about how they're using your data. So if you're concerned about your privacy, it's always best to err on the side of caution and only install apps from developers that you trust.
Selling Data To Third Parties:
Another way that developers make money from free apps is by selling user data to third-party companies. This is why many people are concerned about installing free apps; because they're giving away their personal information with no guarantee of how it will be used.
When an app sells your data, it's usually in aggregate form, which means that your individual information is combined with information from other users before it's sold. So while you may not be worried about a company knowing what movies you watch on Netflix, you might not be so happy if that same company knows what movies you watch AND where you live AND how much money you make.
However, it's important to remember that even paid apps can collect and sell user data without their knowledge or consent; so installing a paid app doesn't necessarily mean that your privacy will be protected either.
Conclusion
As apps can collect data from other apps (even though its rare), it's up to each individual person to decide at the end of the day whether or not they're comfortable sharing their personal information with app developers.
If you're concerned about your privacy, then your best bet is to only install apps from developers that you trust and who have a good reputation for protecting user privacy.
However, even if you do choose to install apps from less trustworthy developers, remember that there are still steps you can take to protect yourself, such as reading through an app's privacy policy before installation and being mindful of the permissions you grant an app when you install it.
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