Tropo

Tropo makes it easy to add voice, instant messaging and text messages to applications. Use our simple API and the web development skills you already know to build powerful communications applications. Create a conference call with one line of code. Answer the phone with a PHP function. Embed a working telephone on a web page with jQuery. Phone calls, speech recognition, and SMS with no telephony hardware, software, or special knowledge needed.

Tropo's cloud API is 100% free for developers around the world. Create your first application in less than 10 minutes at http://tropo.com/.