Android APK, also referred to as application package files are identified with the extension ".apk". This is also the extension of the JAR. If you have a gadget that runs on the Android system, you will find out that there are already APK in it which means that you can install and distribute apps made for the Android system.
It is important for you to know the basics about these files. Actually, most of the Android users are not fully aware of the importance and implication of APK files. While it is true that sometimes you can live with not fiddling much about APK files, it would still be quite useful to learn about it just in case you would need it in the future when you want to download more apps for your Android device.
You can know about apk installer at https://www.phoneyear.com/best-apk-installers-for-android/.
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Important Information About This File
APK file is included in the application that you get from Android Market. Typically, your Android device will automatically install the APK. However, if you have no application from the Android Market, you must ensure that you install it manually on your device. This step is necessary so that your applications will run successfully without any hindrance.
How to install APK files?
Typically, the APK file is installed automatically, especially if the applications from the Android market. If not, you only need to save or copy a file in the memory of your Android gadget. Once you have completed the installation, you should ensure that you manually update the file with the new file export, and copy to another Android device memory.