  Text entry makes up about one-fourth of the smartphone interaction events,
and is known to be challenging and difficult. However, there has been little
study about the characteristics of text entry in the context of smartphone app
usage. In this paper, we present a mixed-method in-situ study conducted in 2016
with 17 active smartphone users to better understand text entry in smartphone
app usage. Our results show 80% of text was entered into communication apps,
with different apps exhibiting distinct usage patterns. We found that
structured data such as URLs and email addresses are rarely typed but instead
are auto-completed or replaced with search, copy-and-paste is rarely used, and
sessions of smartphone usage with text entry involve more apps and last longer.
We conclude with a discussion about the implications on the development of
systems to better support mobile interaction.
