# Part 4: Controlling Worker Activities using TaskRouter.js

In Part 4 of the Quickstart, we tie the earlier aspects of our project together and add a realtime User Interface using TaskRouter.js - the companion JavaScript library to Twilio TaskRouter.

1. [Introducing TaskRouter.js](/docs/taskrouter/quickstart/ruby/agent-ui-introducing)
2. [Add an Agent UI to our Project](/docs/taskrouter/quickstart/ruby/agent-ui-add-project)