extend.bt4.me
Formidable Pro » Bento4Extend
From Strategy11 comes possibly the most advanced and capable forms plugin on the market. It allows an extraordinary array of customization capability form how it appears for the form, to how it is shown to the user after entries are submitted. It is our own personal favourite on the market and we use it quite extensively ourselves. Highly recommended! It also has a lot of plugins available that extends its capability for the end user.