What are some alternatives?
Plivo - Plivo's Voice API enables businesses to build Voice apps to reach customers globally in 200+ countries. Try Plivo's Voice API for free. Instant Sign Up.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Clockwork SMS - Clockwork is an Easy Text Message API. An SMS API for Developers. Build powerful apps and include SMS. Signup is free, Try it now.
Bandwidth - Track your Wi-Fi hotspot usage. Zero configuration required. It just works.
Textlocal - Textlocal is an app that allows for individual and group texting. It is designed for businesses that have employers and employees who need to communicate with each other, making it easier to announce group meetings and special announcements.
HeyWire - Next-level customer service is just a text message away.