The MessageBird Voice Recording cURL Sample Code demonstrates how to record an inbound or outbound leg as part of the execution of a call flow. After a call completes, a recording can be downloaded as a wav file.
Collaboration company 37Signals bought the popular Ember iPhone app, which uses the company's Campfire API (our Campfire API profile) to display and update chats. The app has been renamed 37Signals Campfire and is now available for free (previously $9.99).
The Nexmo SMS API is a service that allows you to send and receive SMS messages anywhere in the world. Nexmo provides REST APIs, but it's easier to use their official Java SDK. This tutorial covers how to send and receive SMS messages with the SDK so that you can use them in your applications.