SurveyJS - Feature rich and open source surveys for embedding into websites.
ProjectHuddle - Get design feedback and client approval using WordPress.
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.
Invision - Prototyping and collaboration for design teams
LimeSurvey - LimeSurvey: the Online-Umfrage Tool - Open-Source Suryeys
Savahapp - The all-in-one design sharing, collaboration, workflow and app prototyping platform