What does APK stand for?
APK stands for Android Package Kit. Likewise other format on your desktop i.e doc, pdf, png, jpg, APK is the package file format for android operating system to install any app on your android smartphone.
For desktops (not Macintosh) if you have idea about .exe files, to run any specific program. So same logic works for android mobile phones. APKs works the same way but for Android devices only. Whenever someone download .apk file then he is able to install app (program) in his/her phone. Mostly aall apps are available on Google PlayStore but there are few reasons you may need to download and install apk. For example if you need a older/previous version of an app but playstore offers only latest version then you need find an .apk of your required version.
What is APK installer used for?
Same as explained above, there are plenty of apps which are not available on Play Store for some reasons, but where there is a will there is way. You can download your APK file of your desired app from any web source and install it manually.
How enable APK install or How to install an APK?
1. Open browser on your mobile phone, search the APK you want to download. Download it.
2. You will receive a pop-up to confirm if you want download. Click OK.
You can see it downloading on the top bar of your device.
If you are prompted to allow installation for Unknown Source, Please go to your mobile settings and enable Unknown Source.
3. Once downloaded, scroll down top bar or go to Downloads, tap on APK file your recently download and tap Yes if prompted.
4. You will see another screen for installation. Click Install .
The app will begin installing on your device.
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