There have so many apps that allow one to run multiple WhatsApp accounts on one phone but with so many drawbacks. Parallel Space and Dual Space are examples of such apps that enables you to install two WhatsApp on one phone.
But now you don’t need any third party apps to use two WhatsApp on the same device. Whatsapp has introduced WhatsApp Business that has business features, unlike the WhatsApp Messenger. WhatsApp Business and WhatsApp Messenger work very well and don’t drain your battery. If you are using an android phone, you can download the App from Playstore.
Although other third-party apps that allow you to use two multiple WhatsApp accounts on one phone still exist, they may find it hard now to convince users to stick with them. I am rocking both WhatsApp Business and the WhatsApp Messenger.