  Determining how voice assistants should broker consent to share data with
third party software has proven to be a complex problem. Devices often require
users to switch to companion smartphone apps in order to navigate permissions
menus for their otherwise hands-free voice assistant. More in line with
smartphone app stores, Alexa now offers "voice-forward consent", allowing users
to grant skills access to personal data mid-conversation using speech.
  While more usable and convenient than opening a companion app, asking for
consent 'on the fly' can undermine several concepts core to the informed
consent process. The intangible nature of voice interfaces further blurs the
boundary between parts of an interaction controlled by third-party developers
from the underlying platforms. We outline a research agenda towards usable and
effective voice-based consent to address the problems with brokering consent
verbally, including our own work drawing on the GDPR and work on consent in
Ubicomp.
