Embed form in email in Rails 3

I want to collect feedback through emails. For this I am thinking of embedding a feedback form in the email itself that the user can fill and submit. Upon submitting, the form will post data to my application where I can process the data.

Please suggest how this can be done or is there any other way I can achieve this.

Note: I also thought about embedding google form in my app but I can't figure out how this can be done. Also, my application is private, so, it can't be exposed to public.