This paper discusses the motivations behind and the characterising concepts of multi-device user interfaces by looking at the main design issues that have been addressed and the various solutions proposed. The discussion of relevant systems and frameworks highlights their main features, which are then used as the basis for comparative discussion. It compares different approaches and perspectives adopted in this area (e.g. responsive design, cross-device, distributed, migratory user interfaces). The features constitute a design space that can be used to facilitate analysis and comparison of tools and frameworks for multi-device user interfaces. Such aspects can be exploited by user interface designers and developers to analyse and compare various options when addressing existing and new applications. The analysis provided may inspire the design and development of new tools and frameworks as well.

中文翻译：

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概念和设计空间，可以更好地理解多设备用户界面

本文通过研究已经解决的主要设计问题和提出的各种解决方案，讨论了多设备用户界面的动机和特性概念。有关系统和框架的讨论突出了它们的主要特征，然后将它们用作比较讨论的基础。它比较了该领域采用的不同方法和观点（例如，响应式设计，跨设备，分布式，迁移用户界面）。这些功能构成了一个设计空间，可用于促进对多设备用户界面的工具和框架进行分析和比较。用户界面设计人员和开发人员可以利用这些方面来分析和比较处理现有和新应用程序时的各种选项。