: Go to your phone's Settings > Security (or Apps & Notifications) and toggle on Install Unknown Apps for your web browser.
: Once the download is complete, tap the file in your notification bar or find it in your Downloads folder to begin the installation. what-is-gb-whatsapp-and-how-to-install-it
: Since the app is not from an official source, it may contain malware or spyware. It does not offer the same end-to-end encryption security guarantees as the official app. : Go to your phone's Settings > Security