Does ClearBoost improve my WiFi connection?

No, ClearBoost addresses your phone's connection to the cellular network. The WiFi connection you use to browse the Web is a different kind of connection, operating on a different frequency than your cellular network. Although ClearBoost will certainly do no harm to your WiFi signal, you will not notice an improvement in your wireless Internet connection. You will, however, notice an improvement if you're accessing the Internet over the cellular network, instead.