Free and popular web form for collecting data and quickly creating a customized web form.
Useful for sending surveys to a given set of users via email or posting a survey on a website to be filled out by anyone. See our case study on implementing a SurveyMonkey integration. Includes a free and paid version.
Easy to use form creation. There is no free version, but the paid version does include payment integration, which can be useful if users will need to input credit card data while completing the form.
This is a plugin for WordPress sites, so it would only make sense to use if you have an existing WordPress website and you wish to manage the form within WordPress. No free version, but paid versions are pretty modestly priced.
Free and paid versions (including more features, payments, and uploads). The API for this web service is quite comprehensive, making it easier to pull in responses, reports and user data.