What are some alternatives?
Twilio - Brings voice and messaging to your web and mobile applications.
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.
Bandwidth - Track your Wi-Fi hotspot usage. Zero configuration required. It just works.
Sinch - Sinch is a powerful voice and messaging SDK that lets you bring your apps to life with VoIP and...
VoxImplant - Voximplant is a software program that allows businesses to automate communications by setting up automatic communication systems in the cloud.
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.