Is there sufficient colour contrast ratio of all text against the background colour?
When colour is used to show information, is it supplemented with text, icons, or other visuals to communicate information?
Do all links clearly describe the page that will load or what will happen when a person clicks or presses them?
Is the interface fully keyboard accessible? Can a person use a keyboard alone to complete all tasks, and get access to all information?
When a user makes a mistake completing a form or a transaction, are the errors identified? Is clear feedback provided to the user as to how to resolve the error?