  Online services like Google provide a variety of application programming
interfaces (APIs). These online APIs enable authenticated third-party services
and applications (apps) to access a user's account data for tasks such as
single sign-on (SSO), calendar integration, and sending email on behalf of the
user, among others. Despite their prevalence, API access could pose significant
privacy and security risks, where a third-party could have unexpected
privileges to a user's account. To gauge users' perceptions and concerns
regarding third-party apps that integrate with online APIs, we performed a
multi-part online survey of Google users. First, we asked n = 432 participants
to recall if and when they allowed third-party access to their Google account:
89% recalled using at least one SSO and 52% remembered at least one third-party
app. In the second survey, we re-recruited n = 214 participants to ask about
specific apps and SSOs they've authorized on their own Google accounts. We
collected in-the-wild data about users' actual SSOs and authorized apps: 86%
used Google SSO on at least one service, and 67% had at least one third-party
app authorized. After examining their apps and SSOs, participants expressed the
most concern about access to personal information like email addresses and
other publicly shared info. However, participants were less concerned with
broader -- and perhaps more invasive -- access to calendars, emails, or cloud
storage (as needed by third-party apps). This discrepancy may be due in part to
trust transference to apps that integrate with Google, forming an implied
partnership. Our results suggest opportunities for design improvements to the
current third-party management tools offered by Google; for example, tracking
recent access, automatically revoking access due to app disuse, and providing
permission controls.
