1 If there is no update, 2 Go to Settings 3 Go to Apps Settings 4 Click on All Apps
Go to File Manager Copy the folder of Gb Whatsapp to SD Card or inside another folder, Uninstall Gb Whatsapp App, Install the one you downloaded v15.0, Go to File Manager again, Now your Gb will become the new folder of whatsapp,
Where you copied the folder of Gb Whatsapp, from there again paste the Gb Whatsapp folder in the internal storage, If Already Name is said, Paste all the files from the old folder to the new one. Now open Gb Whatsapp App,