In this chapter, we covered the fundamentals of the Twilio Client: what it is and how it works at a high level, before integrating it into a PHP application in the browser for both incoming and outgoing calls with full code samples.

We also briefly considered how to use Twilio Client in a mobile app for iOS or Android.

In the next chapter, we'll put together what we've already learned, building two exciting projects using the Twilio platform: a "request a callback" tool for your website and a conference calling service.