GetChat.App - Add WhatsApp chat to your website for free
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
BlueReceipt - Text marketing customers love ❤️
Talkus - Chat with your website users from Slack
Textedly - Textedly is an SMS marketing communications channel that allows to advertise, promote, announce, and engage with audience through text messaging directly to cell phones.
Drift - A messaging app that helps you grow your business.