Amelia is described as 'Automated booking tool for WordPress handling 16,000 weekly appointments, 20,000 monthly events, with payment integration and customizable features' and is a appointment scheduler in the office & productivity category. There are more than 25 alternatives to Amelia for a variety of platforms, including Web-based, SaaS, Wordpress, Self-Hosted and Google Chrome apps. The best Amelia alternative is Thunderbird Appointment, which is both free and Open Source. Other great apps like Amelia are Lunacal, Calendly, Supercal and TidyCal.
Zencal is like Calendly, but free and with better teamwork. It allows you to add multiple teams and sync everyone’s calendars. It's easy to sell meetings as a subscription and multiple meetings in a batch.
Poland
EU