Klaviyo - Klaviyo helps brands own the customer experience, grow higher-value relationships, and deliver more personalized marketing experiences across email, mobile, and web.
Twilio - Brings voice and messaging to your web and mobile applications.
Campaign Monitor - Email marketing software built for designers and their clients to run successful email campaigns.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
TargetBay - TargetBay is a complete eCommerce revenue generation platform.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates