For Android 4.4.2: Whatsapp

Even if an older version of the app is already installed, WhatsApp frequently forces updates to maintain its end-to-end encryption and server compatibility. Eventually, the app will display a "Date is inaccurate" or "Update WhatsApp" message that prevents any further use [3, 4]. Why Support Was Dropped

Once installed, follow these steps to verify your phone number: whatsapp for android 4.4.2