The standard way to render a <form> in Phoenix used to be the form_for/4 helper, but recent versions of Phoenix added a new function component called <.form>, AKA Phoenix.Component.form/1.

I wasn’t sure when to use form_for/4 instead of <.form>, but it turns out that the answer is “never”. I wrote up my full findings here:

https://phoenixonrails.com/blog/you-can-stop-using-form-for-in-phoenix