Amazon SES - Scale your business email & marketing messages with Amazon Simple Email Service (SES), a cost-effective and reliable cloud email service. Sign up today.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Mailgun - A set of powerful APIs that enable you to send, receive and track email from your app effortlessly whether you use Python, Ruby, PHP, C#, Node.js or Java.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Mandrill - Mandrill is a new way for apps to send transactional email. It runs on the delivery infrastructure that powers MailChimp.
Plivo - Plivo simplifies your customer engagement.