I’m still getting comfortable with Burp Suite (http://releases.portswigger.net/2014/07/v1603.html) but this new version looks impressive (especially since I don’t understand what half the new features mean :-) ). I’m currently getting up to speed on Zed Attack Proxy (https://www.owasp.org/index.php/OWASP_Zed_Attack_Proxy_Project) as that one seems to be a bit more aimed at people getting up to speed on Webapp pentesting.