Although Yola has more than 270 themes for their customers to choose from, nearly all of these themes are outdated to the point of incompetence. Yola would have been a fantastic site builder if you were building a website back in 2008. However, in the modern world of web design with responsive themes, video backgrounds, and exceptionally complex interfaces, Yola simply cannot compete with any of the major site builders out there.
Gator Website Builder has more than 200 templates that are professionally designed and available for free. And yes, all of them are mobile design compatible. You don't need to do anything to activate the mobile design. Gator does allow you to edit the content in your mobile version without affecting the desktop version. Editing content on the mobile version can be handy if you have special mobile-only sales or if you want to optimize the experience people have on their phone.