Whenever a user connects with more that one single device, either sequentially or concurrently, to a liquid Web application, the application adapts to the set of connected devices and it is able to flow seamlessly between them following the user attention. As opposed to traditional centralised architectures, in which the data and logic of the application resides entirely on a Web server, Liquid software needs decentralised or distributed architectures in order to achieve seamless application mobility between clients.
By decomposing Web application architectures into layers, following the Model View Controller design pattern, we define a maturity model for Web application architectures evolving from classical solid applications deployed on single devices, to fully liquid applications deployed across multiple Web-enabled devices.
The maturity model defines different levels based on where the application layers are deployed and how they migrate or synchronize their state across multiple devices. The goal of the maturity model described in this paper is to understand, control and describe how Web applications following the liquid user experience paradigm are designed and also provide Web developers with a gradual adoption path to evolve existing Web applications.