f you’ve ever used an Android phone, you’ve encountered an APK. Short for Android Package Kit, an APK is the standard file format for installing and running applications on the Android operating system.
As of November 2025, there are more than 2.3 million Android apps in Google Play Store, which is the normal go-to destination for downloading APK-based applications. These applications have become part and parcel of everyday smartphone use for an estimated 4.9 billion users worldwide - nearly half the world’s population - which means a good understanding of how these apps work is of global importance.
There are far more places than just Google Play Store to download APK applications, and while many of them are safe and legitimate, there are also some pressing security risks to bear in mind. In this guide, we’ll look at the basics around APK security: how to install APK apps, the biggest risks to users, and how to practice APK-safe activity on your smartphone or tablet.
How does an Android Package Kit work?
APK files are normally created by App developers using Android Studio, which is the official Android development tool. Completed app designs are then compiled by the development app and translated into an APK file. This file will contain all the key information that the application needs to run successfully, including:
- Manifest information like name, version, and access rights
- Assets and resource files
- A directory for storing resources information
- Compiled code and native libraries
There is a size limit of 100 megabytes for APK files to be hosted on the Google Play Store. When developers want to create more detailed apps - especially those that require extensive use of large assets like images, videos, and graphics - they can create a maximum of two APK expansion files for that purpose.
Where to download APK files and how to install them
There are
two main ways to install APK files on your Android-based device. As you’ll see
here, one is much simpler than the other:
Using Google Play Store
The first
way (and the one you’re probably already familiar with) is to search for and download
the apps you want through the Google Play Store. This plug-and-play setup is
specifically designed to make it as quick and easy as possible to get started
with your chosen apps. If the app isn’t available free of charge, then the
integrated payment options within your Google Play Store account will allow you
to pay at the point of download in a matter of seconds.
Installing APK files manually
The alternative method for installing APK files is to ‘sideload’ them from third-party download and file transfer sites. To do this, you will most likely have to adjust your device’s settings to allow these downloads to be accepted. This can be done as follows:
- Go into your Settings and open the ‘Apps’ folder (this may be called ‘Apps and notifications’ on some devices).
- Look for the settings within this app, and within that, select ‘Install unknown apps’.
- Select the application that you want to use to download your APK file and set it to allow this will typically be your chosen Internet browser such as Chrome.
However, it’s extremely important to note that installing APK files manually can open your device and data to a huge range of security risks. We’ll explore those risks and how to protect yourself against them later in this article.
Is it possible to install APK files on non-Android devices?
With the right tools in place, yes. For example, Windows Subsystem for Android is a downloadable application for Windows 11 that allows users to download Android applications available in Amazon’s App Store and run them on a Windows device.
It’s also possible to deploy an Android emulator to open APK files in Windows, working to a similar principle as the emulators that run retro games. This approach is the only way to open APK files on Apple’s iOS operating system. However, it isn’t possible to install and run APK files in iOS directly.
What are the major APK security risks?
Like any kind of application file, APKs cannot be considered 100% safe. Even though Google has acted over the years to minimize the risk to users, there will always be dangers wherever an application is downloaded from. These potential risks include:
Malware, Viruses, and Ransomware
Just like any other type of software, there are bad actors out there who will create deliberately malicious apps. These will intend to infect a device with a virus, or with ransomware that restricts device use and demands payment from victims in return for restoring the device to its original state. Often, these apps are convincingly disguised as legitimate apps with practical uses just like any other, which heightens the need to stay vigilant and always take protective measures.
Loss of device control
Connected
to the previous point, malicious apps can be used to gain root access to, and
even take control of, entire devices. This means that cybercriminals have command over how a device is
used, and can put it to their own malicious ends, from accessing user bank
accounts to conducting their own criminal activities.
Theft of sensitive data
In either of the first two cases, personal data, sensitive digital assets like passwords, and even funds within bank accounts can be considered at risk. Data theft can cause untold damage to a user’s personal life, and if a device used for business is affected, can have major impacts on the organization from legal, financial, operational, and reputational perspectives.
Illegal or pirated apps
Some APKs are created as a way of bypassing paywalls on legitimate apps so that users can access content and features for free. This is illegal and may lead to problems further down the line. Similarly, many hackers use APKs as a way of getting hold of new apps and releasing them to the public before their official launches. This can pose operational risks to the device if the code in the leaked APK is incomplete.
Are Rogue APKs Threatening the Security of Your Phone?
Third-party Android applications are a growing threat. Safeguard your smartphone against malware aimed at stealing your personal data.
Try Premium for FreeHow to make your Android phone activity APK-safe
As with most areas of cybersecurity, risk mitigation starts with the user. While technology can support by detecting and responding to threats and malicious activity, adopting good security practices can reduce the chances of these bad APK files even becoming a problem. This includes being cautious about app sources, keeping your device updated, and using a trusted antivirus product for added protection. We recommend a combination of the following:
Stick to Google Play Store and other reputable sources
First, you should only download APK files from platforms and sources that you completely trust (which is good advice for any type of application), so Google Play Store should always be your first port of call.
This is not only because it scans all apps submitted to the platform before they’re released to the public, but also through its Google Play Protect feature which will scan apps at the point when you download them, scan apps for malware on a regular basis, and verify any new upgrades and installations post-download.
Check reviews from other users
Even with those protections in place on Google Play Store, it is still possible for some well-designed malicious apps to slip through the net - and this is where the global Android community comes in.
Online users generally aren’t shy in letting their feelings be known when an app doesn’t meet their expectations, and the same applies if an app is malicious - or even just if it looks a bit suspicious. Before downloading any app, a read through its user-submitted reviews and a check of its star rating can indicate if there are any problems that other users have already encountered.
Update apps regularly
Most good apps will release updates periodically, either to fix any bugs that have been identified, or to introduce new functions and features. More importantly, updates can also close off any potential security vulnerabilities that hackers and cybercriminals could exploit. That’s why it makes sense to download and install new updates as they become available; the more often you use an app, the more often you should look for updates.
Update your Android OS regularly
The same principle applies to the wider Android operating system, where updates and security enhancements are available on a regular basis. Ensuring the most recent upgrades and patches are in place ensures that any vulnerabilities in older versions, that cybercriminals have had time to try and exploit, are eliminated from the device.
Manage app permissions
Different apps have different permission levels around what they can and can’t do with data on the device (like images and contacts) or other app functions (such as location). Newer versions of Android have a feature called ‘automatic permission reset’, where any apps that haven’t been used for three months have their permissions turned off. However, you should always regularly review the permissions on the apps you use the most and turn off those that aren’t necessary.
Delete apps you no longer use or need
It’s easy for the number of apps on a device to balloon over time, and for apps that you previously used regularly to fall out of favor. If an app is no longer needed, then there’s no reason not to delete it, and remove any risk of malicious activity (however small that risk may be) coming through that app. This also has the added benefit of freeing up storage space on the device, which in turn can help it run faster and more efficiently.
Use malware protection solutions
Smartphones and tablets need antivirus and anti-malware protection just like desktop computers and laptops do, and that protection needs to be specialized to the type of threat that APK files can pose. For example, Kaspersky Mobile Security uses real-time virus detection and response measures, blocking and protecting against more than 5.6 million mobile malware, adware, and riskware attacks every quarter. Combined with the security best practices listed above, it gives you the best possible chance of minimizing your risk of malicious APK files, so that you can use your smartphone or tablet with confidence.
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