Use APKPure App
Get Update Whatsapp old version APK for Android
“Update Whatsapp” will check and update available new version from official website of Whatsapp. You can install this application on your Android tablets and smart phones.
It is known that Whatsapp is updated to new features and fixed bugs more often than in the store. This application gives you opportunity to check whether new versions are available and then update it!
Mainly, keep in mind that we are not part of Whatsapp. Therefore this application is not official.