Habit development is a central theme when exploring long
term behavior change. Implementation intention can support
conscious creation and formulation of a habit, while rehearsal
can support the need for repetition of the target behavior in a
consistent context until the habit becomes automatic. This paper
describes an exploratory study in which a virtual assistant
is utilized to support implementation intention and rehearsal
over a 4 week period. We describe the findings and experiences
with creating and formulating habits with a virtual assistant
and rehearsing it over time to develop it as a habit. Habit
development was measured throughout the study with the Self
Report Behavioral Automaticity Index and self-reported adherence.
The assessment was further supported with in-depth
interviews at the end of the study period. We found an overall
acceptance of both the concept of creating and rehearsing an
implementation intention with a virtual assistant. Our results
suggest that there are many opportunities for improving the
use of virtual assistants for habit development. We summarize
the most important findings and present a set of design
recommendations for developers and future research.