Mailchimp & checkbox
Problem: pass info from check-boxes Contact Form 7 or any other form to Mailchimp.
Solution: By default Mailchimp don't support check-boxes. Solution lies in the create groups in Mailchimp or get data using JQuery from necessary fields, then add data to hidden fields and after then send it to Mailchimp.
MailChimp handles their information very specifically: Fields are for information about each subscriber that help you identify them (first name, last name, email, city, state, gender, etc). Fields do not allow for checkboxes. Then you have groups, which are basically ways to organize your subscribers based on their interests. You create a group, give it a name, and enter your choices. Here is where you can use checkboxes, or you can use radio buttons or dropdowns. You would use groups to ask something like "What topics would you like to receive emails about?" or "What sports are you interested in?" You can then create segments based on fields, groups, or both. Once you generate a segment, you can then send a mailing to that segment.