Kannel - Open Source WAP and SMS Gateway
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Ozeki NG SMS Gateway - Ozeki NG SMS Gateway is a powerful, reliable and flexible SMS Gateway application.
Twilio Flex - The programmable contact center platform 📱
KAPSYSTEM - KAP Computer Solutions Pvt. Ltd.,
Drift - A messaging app that helps you grow your business.