In this tutorial, we'll demonstrate using the Twilio Client iOS SDK to make an outgoing call, receive an incoming call, and make calls between two Twilio Client devices.
This guide assumes you have familiarity with iOS and Objective-C concepts like View-Controllers, delegates, properties, and Objective-C object lifecycle and memory management.
Install Xcode with at least iOS SDK 4.2 or higher. Xcode may be obtained from the Mac App Store or by downloading it from http://developer.apple.com.
You must be a registered iOS developer with valid Provisioning Profile(s) for any devices you will be testing with. For more information on provisioning devices, please refer to Apple's documentation "Managing Devices".
You will need your Twilio Account SID and Auth Token to initiate calls from your iOS device. You will find these in your Account Dashboard. If you don't have an account, sign up for a free trial account.
A Twilio Application SID. Visit the Apps tab to create an Application.
You can find all of the code from these tutorials in the 'Quickstarts' folder of the iOS SDK download.