Voxbone - Fully compliant, enterprise-ready voice and SMS on demand. Build local presence on a global scale with elastic SIP trunks and phone numbers. Try for free.
Clickatell - Simple, reliable mobile messaging cloud.
Twilio - Brings voice and messaging to your web and mobile applications.
ShoutOUT - All in one business texting tool to send personalized alerts, promotions, reminders, short links and marketing campaigns, for any SMEs (hotels, restaurants, education, non profits, Woocommerce, banks, healthcare, agencies, supermarkets, weddings)
Bandwidth - Bandwidth offers SIP trunking, Emergency communications, and Voice & Messaging APIs.
Trumpia - SMS Marketing and Marketing Automation software for Mass SMS, internal communications & emergency alerts. #1 Text Messaging Service used by Fortune 500s.