SurveyJS - Feature rich and open source surveys for embedding into websites.
Adobe Campaign - Adobe Campaign provides campaign, offer, and personalization management capabilities.
Survey Monkey - Create and publish online surveys in minutes, and view results graphically and in real time. SurveyMonkey provides free online questionnaire and survey software.
HubSpot Marketing Hub - HubSpot is a cloud-based inbound marketing software that allows businesses to transform the way that they market online.
LimeSurvey - LimeSurvey: the Online-Umfrage Tool - Open-Source Suryeys
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.