Sales Essistant is described as 'SalesEssistant (SE) is an online platform that allows websites to collect facts about individual users in real-time. This information is often described as customer intent or visitor intent'. There are more than 100 alternatives to Sales Essistant for a variety of platforms, including Online / Web-based, iPhone, Android, Windows and SaaS. The best alternative is LimeSurvey, which is both free and Open Source. Other great apps like Sales Essistant are UseResponse (Paid), SurveyMonkey (Freemium), SurveyJS (Free Personal, Open Source) and Zendesk (Paid).
LimeSurvey (formerly PHPSurveyor) is an Open Source PHP web application to develop, publish and collect responses to online & offline surveys. Anonymous and Not-Anonymous survey, open and closed group of participant surveys, optional public registration for surveys.
Unlike the most others solutions, SurveyJS Project consists of three fully independent parts: run-time SurveyJS library, SurveyJS editor and SurveyJS service for storing and analyzing results. You may stick with the complete solution or use only a library.