GRAVITY FORMS is a complete contact form solution for WordPress. You can build complex, interactive contact forms in minutes. GRAVITY FORMS can be used for contact forms, WordPress post creation, calculators, employment applications and more. GRAVITY FORMS have add-on integrations for popular web applications and online services like SurveyMonkey, Slack, Trello, Stripe, PayPal, and many more. GRAVITY FORMS is open source and GPL licensed. All of the code included is unencrypted and easy to modify. It has tons of hooks and filters to let you customize to your hearts content.