Twitter tools is a Chrome add-on developed by Patrick Mackaaij that provides a convenient way to analyze your Twitter account. After setting up your Twitter account name, clicking the button opens a popup that shows links to a few Twitter tools.

One of the tools available is DoesFollow.com, which allows you to check whether a Twitter user is following your account. This can be useful for determining your reach and influence on the platform. Additionally, you can click through to twtrland, Klout, PeerReach, or Kred to check the users' scores or profile analysis. These tools provide insights into the users' engagement and influence in the Twitter community.

Another feature offered by Twitter tools is the ability to draw a Venn diagram of your followers. This allows you to see how many and which accounts read along with your replies. The Venn diagram is drawn by Followerwonk.com, providing a visual representation of your Twitter audience.

Overall, Twitter tools is a helpful add-on for Twitter users who want to gain a better understanding of their account's performance and analyze their followers. It provides easy access to various tools and analytics, making it a valuable resource for anyone looking to optimize their Twitter presence.