Currently, the update (version 2.12.38) is only available from the WhatsApp website, which will require you to have app side-loading enabled on your smartphone to install apps from unknown sources. It's a welcomed update and one we're sure fans of the service will enjoy using.
The visual refresh really makes for an inviting experience, and one you will want to continue using. We'll also give you all a heads up as to when the update is available through the Google Play Store. for now, you can download the APK file from WhatsApp directly by hitting the link below.