Everything You Need to Know About APK Files

Even if you’re an Android phone user, you might not know what people mean when they discuss an APK file. Put simply, an APK file is created by Google exclusively for the Android operating system. Most APK files come pre-installed, or “native,” to the Android mobile device, whether it be a smart phone or tablet. However, that doesn’t mean they’re useless like temporary files or cache.

In fact, you likely will not see an APK file because many Android operations happen behind the scenes. However, users are likely to notice them if they examine the files of a downloaded app from the Google Play store.

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What’s in an APK File?
As mentioned, an APK file is designed exclusively by Google for Android’s operating system. The content of some common APK files explain why. The META-INF contains what is known as the manifest file. Think of this as the main file, which contains the file’s signature and the resources within the APK file. After that are the Lib/ and Res/ files, which contain the native library and further resources, such as images, within the APK file. An AndroidManifest.xml file describes the name, version, and contents of an APK file. Think of this like a more robust version of the META-INF file. Lastly, the classes.dex and resources.arsc files contain compiled Java classes and resources, like strings, to be run on your Android device.

Looking at an APK File
Viewing APK files is actually quite easy. In fact, they even have their own folder. Simply locate the APK file you want to see and click it. APK files are stored in a .ZIP file, which compresses all the information within the APK file into a single file. This is used to save storage on your device. By clicking, or unzipping, the file, you’ll be able to view the contents within the file. Note, however, that you may have to rename the file “.zip” before opening. Alternatively, you can also open the file through the Zip application’s “open dialogue” box.

Creating an APK File
Feeling crafty? Actually designing an APK file, which you can use for your own app or for beta testing an app, isn’t that difficult. You can design an APK file using the Android Studio, the official integrated device environment (IDE) available for Android software developers. It’s available for Windows, Mac, and Linux and allows users to design APK apps for the Google Play store.