Slack with your Users - Speak to your app's users entirely within Slack
OnWhatsApp - Create your online catalog, receive orders on WhatsApp 🛒
Conversity - Easiest way to manage Facebook Messenger chats
Smooch.io for WhatsApp - Engage with your customers on WhatsApp like never before
Avochato - Text messaging for your business.
WhatsApp for LiveChat - Let your customers reach you via Whatsapp