Technologies may support older adults in their aging process. However, to be useful, they have to be accepted. Existing technology acceptance models are not well adapted into the gerontological context. These models probably neglect aging-specific acceptance factors. The aim of this study is to understand the technology acceptance process by the older people. We develop an inductive and empirical approach for conceptualising the acceptance dimensions related to the biopsychosocial experience of aging. We used an adaptation of the Grounded Theory (GT) methodology to investigate older participants’ experience during the participatory design of an interactive calendar called Amelis. Both the design studies and the usage studies highlight that Amelis can be useful for the elderly in different ways. Nevertheless, we identify barriers to the use of such technology. They are related to the learning process, the credibility of the electronic device, and various loads for users (i.e. cognitive, emotional, physical). Understanding user experience represents the empirical basis of the GT. The GT results emphasize that time is a key concept to analyze technology acceptance by the elderly. Three conceptual dimensions appear regarding time: chronological, adaptive, axiological. The gerontological context gives precise meaning to those dimensions. Accordingly, technology acceptance by the elderly especially depends on (1) specific moments (2) adjustment process regarding aging changes (3) time value. Underlining the importance of time provides directions for further research within the elderly. It also supports the evolution of professional practices as well as institutional choices.