Final answer:
Appy Pie is the app that lets users automate mobile UI with no code, while the other options have different functionalities in the field of automation and app development.
Step-by-step explanation:
The application you're referring to that enables users to automate mobile user interfaces without writing any code is Appy Pie. It allows individuals to create their own apps through a no-code development platform, utilizing drag-and-drop components to build the application. The other options listed serve different purposes; for example, AutomateIt is more focused on automating tasks on your device, UIPath specializes in robotic process automation mainly for enterprises, and Bubble is a no-code platform specifically designed for web applications rather than mobile UI automation.