It provides a faster way to get to navigate the game.
For example, on the default Action Bar, the far right button takes you to Tokoloshe’s Addon Gallery where you can access very cool gameplay enhancers.
The Action Bar can be significantly upgraded with the purchase of the Extended Action Bar, which adds a toggle for a second row of navigation buttons to access more places. If that's not enough, it also adds on-bar notifications for special alerts to unlocks, messages, and more. It's an all-around better gaming experience - plus, any Addon you purchase will kill the ad bar in the game.
Talk about Add-ons and other topics in our Community Discussion area ^V^