WhatsApp is not only available for Mac or Windows PC, but also for mobile devices such as Android, iPhone, and Windows Phone. That is the reason why a lot of people manually download WhatsApp from a variety of online sources. Here is one way of downloading WhatsApp for your Android devices.
Downloading WhatsApp is also useful if you are going to update WhatsApp manually. Basically, you can do it for your Android device by visiting this website https://www.whatsapp.com/android/. Otherwise, you can download the updated file via APK Mirror.
However, if you are willing to get beta versions of the app via the Play Store, then you can sign up via this link https://www.play.google.com/apps/testing/com.whatsapp. As a result, you would acquire the latest features even before your friends do.
After downloading the WhatsApp file, you need to install the APK file. Nevertheless, you have to check it from Settings > Security > Unknown Sources. Just ensure that the toggle is on for unknown sources. This would allow the installation of files from third-party sources. But, it is recommended that you toggle back to its default position to avoid accidentally downloading and installing malware on the device.
APK files can be installed either on your phone or tablet. You simply have to search the downloaded file by opening the file explorer app from your phone or tablet. This can be found at the folder named Downloads. Once you have found the APK file for WhatsApp, just tap on it and the rest will be up to your device as you can see it in action at the top bar of the device.
Take note that after you download WhatsApp, you can immediately install it by tapping Yes to confirm when prompted. The app will automatically be installed on your device while you wait a few seconds to finish.