SocialEpoch is the finest option if you're looking for a complete WhatsApp marketing solution for your business. Thanks to features like its close integration with Shopify, multichannel chat widget, and shared inbox, WhatsApp has everything you need for business marketing.
On the other hand, if you're merely interested in mass WhatsApp messaging for your business and don't need (or want to pay for) extra features, SocialEpoch would be a great option with its anti-blocking technology.
Whatever application you finally choose to use, always follow WhatsApp broadcast best practices to avoid getting blacklisted and having your users designate your messages as spam. After all, you wouldn't want to just aim to alienate customers.