I have taken out my SIM card and SD card as I have a new phone, how do I delete whatsapp, as messages are still being received to my old phone?
Uninstall Whatsapp from Google Play or from the phone's Application Manager (In the Samsung Galaxy S4,
Settings > More > Application Manager).
If it's a pre-installed app and cannot be uninstalled by regular means, clear its data via Application Manager. In the Application Manager, click Whatsapp and you might see buttons like
Clear data and
Just install the WhatsApp on your new phone, and sign-in with the same number. WhatsApp will automatically stop forwarding the message to your old phone, and you'll start receiving the messages on your new phone.
To uninstall WhatsApp from your phone, you can go to
Settings > Application Manager > Scroll down to WhatsApp > Click on it > Click on uninstall and you are done.