A common cause for inconsistent accessibility in the design of ICT applications is that designers work to develop optimal and satisfactory interfaces but they do not take care to comply with all users' needs and possibilities to access. The study presented in this paper stems from a lack of published evidence able to support designs in developing accessible interfaces for websites, mobile apps or conversational Interfaces (chatbot or voicebot). This work aims at investigating accessible design patterns that can be used by designers to implement applications accessible by multiple devices. To solve this problem, we propose a design pattern language able to provide WCAG compliant design out-of-the-box solutions. The navigation through the design patterns allows designers to gather existing solutions based on solid evidence and examples to develop inclusive applications accessible by web, mobile devices or conversational agents.
Keywords: Accessibility pattern language; Chatbot; HCI design patterns; Inclusive design; Web and Mobile design.