  In the attention economy, video apps employ design mechanisms like autoplay
that exploit psychological vulnerabilities to maximize watch time.
Consequently, many people feel a lack of agency over their app use, which is
linked to negative life effects such as loss of sleep. Prior design research
has innovated external mechanisms that police multiple apps, such as lockout
timers. In this work, we shift the focus to how the internal mechanisms of an
app can support user agency, taking the popular YouTube mobile app as a test
case. From a survey of 120 U.S. users, we find that autoplay and
recommendations primarily undermine sense of agency, while search and playlists
support it. From 13 co-design sessions, we find that when users have a specific
intention for how they want to use YouTube they prefer interfaces that support
greater agency. We discuss implications for how designers can help users
reclaim a sense of agency over their media use.
