Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.

Jasmin SMS Gateway - Jasmin is a very complete open source SMS Gateway with many enterprise-class features such as:

Drift - A messaging app that helps you grow your business.

Ozeki NG SMS Gateway - Ozeki NG SMS Gateway is a powerful, reliable and flexible SMS Gateway application.

Twilio Flex - The programmable contact center platform 📱

Bulk SMS Services - Sending Bulk SMS to the customers will engage the customers with your business and new offers.