iOS 12 focused on "under the hood" features. iOS 13, however, is ". . . easily the most power-user-focused iOS update that we have seen in the history of the OS." For the long list of new features (over 200!), go to 9To5Mac's post, Hands-on with 200+ iOS 13 changes and features and/or watch his 45 minute video:
Want details about accessibility-related new features? AppleVis (Dave Nason and Thomas Dornville) interviewed Sarah Herrlinger, Apple's Director of Global Accessibility Policy and Initiatives; and Dean Hudson, Apple's Accessibility Evangelist. In the interview, numerous new accessibility features were discussed.
Important Note: Accessibility Settings has moved up and is now under Settings > Accessibility (no longer under Settings > General > Accessibility.
The Apple ToolBox blog post, provides detailed instructions, pictures and practical hints of mouse support for iPad, iPhone and Voice Control, and more.