MessageBird Chat API - Connect with your customers through different messaging apps
Twilio Flex - The programmable contact center platform 📱
Voiceflow - Build voice apps in your browser without coding
Jovo - 🗣 Build cross-platform apps for Alexa and Google Home
MessageBird API on StdLib - Purchase numbers, send SMS and more with one line of code
LoopMessage - LoopMessage is a perfect macOS tool for personalized mass messaging via iMessage/SMS, WhatsApp, Facebook Messenger, Telegram, Viber, and Skype.