I'd like to collect email addresses of people for my email campaigns in live events I organize. These events take place often in places where i'm not connected to the internet and therefore I would need to do so offline. And since I live in Spain I want them to be GDPR compliant (allowing me to set up a checkbox in which people can tick to what they sign up, showing explicit consent
Do you know of any free opt-in forms offline that would be GDPR compliant? Ideally I would want a form that I could sync automatically with my Mailchimp account, but otherwise, any such form that would enable me to collect contacts in a Google Sheet would work fine.
Thank you very much,