The free Touch Starter pack offers full access to all Touch channels for one agent seat. It also offers access to all the features of a Touch Standard package such as the Unified Chat Desk, sentiment analysis, customized branding, and automated welcome and away messages. You can add as many agent users as you like to your free Touch account, but only one agent will be able to log in (per agent seat) at any given time. If you want more than one agent to log in at the same time, you'll need to upgrade to Touch Standard and purchase more agent seats. Twitter charges a small monthly fee for use of its API for businesses and you will need to subscribe to make use of this channel. The same fee is charged across all Touch packages.