Treemily is described as 'online family tree builder that helps users create diverse visualizations of their families. The platform is free for all basic functionality and family tree designs, with paid membership options available for access to more robust customization options'. There are three alternatives to Treemily, not only websites but also apps for Windows and Mac. The best alternative is My Family Tree. It's not free, so if you're looking for a free alternative, you could try Simple Family Tree.
My Family Tree is a genealogy product for all keen family historians. Its modern user interface and wide range of features will help you create your family tree in no time at all. Features Interactive and customisable family tree chart viewer.
Simple Family Tree enables you to create and/or view a family tree. It displays ancestors and descendants of any selected individual (it reads and writes files in Gedcom format). You can enter notes, events, marriage details, and an alternate name for each individual.