MessageBird!

Twilio is a web-service API that lets you use your existing web languages and skills to build voice and SMS applications. We focus on building a simple, powerful, pay-as-you-go communications platform so that you can focus on what you do best.

Plivo is a voice and SMS API platform that enables developers and enterprises to build powerful apps with great features. With 24/7 free tech support and low prices, Plivo can help your business scale globally.

Receive & send SMS messages, allocate phone numbers, control incoming phone calls, build IVRs, connect calls and create automated outgoing phone calls. Simply Voice, SMS & MMS in one easy API.

Reach any customer on any mobile phone, anywhere, today!