A case study on defining simplicity in interaction design: A review of the schematic and functional evaluation of the simple mode smartphone interface

In the last decade, with the development of technology and the widespread of digital product designs, users have become the main element in the field of interaction design. Academic studies and sectoral product designs conducted under the title of user-centered interaction design created the need to develop discussions on the concepts of simplicity and usability and to make definitions that explain these concepts. In the context of contributing to these discussions and creating definitions, this study aims to analyze the simplicity features of a product developed for simplicity and to measure whether the simplicity offered by this product is meaningful to users. In addition, it is aimed to reveal the effectiveness of the decisions taken for simplicity for the user by comparing it with the version of the presented product that does not claim simplicity. In order to answer the research questions, first a content analysis study and then structured interviews were conducted with 12 interviewees. SUS-TR and EWPL-TR tests were used for user reviews. The findings show that there are design and functional differences between the simple product and the standard version of the product. Simple mode product's usability level is at marginal and acceptable levels. However, it could not be concluded that the decisions taken for simplification create usability for all users. Especially, it has highlighted that simplicity may be useful according to its relationship with user needs. In summary, there is a positive correlation between making user-centered and balanced design and functional decisions and creating meaningful simplicity.