Yes, whatsapp can transfer from iPhone to new iphone by iCloud Backup or without iCloud by selecting "Chat Backup" from "Chat Settings" on whatsapp or by a tool called AnyTrans.
You can also use WhatsApp Transfer Tool to transfer, backup & restore WhatsApp without any limitation.
Also, through iTunes Backup, you can restore WhatsApp.
Transfer of whatsapp can also be done via email but it can only transfer one conversation at one time.