jQuery UI is what allows the creation of widgets for all the different platforms. It is used for creating the most popular mobile web applications and widgets. jQuery Mobile is the native mobile application development framework that allows the creation of natively mobile applications.
jQuery UI is the library that is used to create widgets for all the different platforms. This is used for creating the most popular mobile web applications and widgets.
You can think of jQuery UI as being a layer that comes between the client and the server. It is used to create the most popular native mobile applications. For any HTML applications that are not natively mobile applications it is not necessary to use jQuery UI. The only difference between a jQuery UI application that is not natively mobile and a native application is that the client must be able to connect to the server to create the application.