ToCustomers works in the background of a landing page, executing constant AB tests- analyzing user behaviour to make improvements to the current page. Once it finds a better-performing UI/visual experiment - it uses that as the current landing page.
SuperWordly gets the plain English meaning of words you don't know while reading in context. Once a week, you receive an email with a selection of 5 words you have added, with examples of usage and prompting you to use these for a week.