Amazon recently announced the Reminders API. The API allows Alexa skills developers to create and manage reminders for users. For example, once integrated, Alexa could remind a user about an upcoming meeting 30 minutes beforehand. On the flip side, Alexa can also help a user start the day by telling the user when 30 minutes are free.
KAYAK and the NHL have been successful early adopters of the Reminders API. KAYAK uses the API to inform KAYAK users when a tracked flight lands. Check out the KAYAK skill to learn more. The NHL uses the API to alert fans 30 minutes before a favorite team starts a game. Check out the Official NHL skill to learn more.
Two sets of permissions are needed to enable the Reminders API. First, you need global reminders read/write permission. Second, the end user must explicitly grant permission to set a reminder through the applicable skill. To add reminders, configure your skill in the Permissions section of the Amazon Developer Portal. Next, implement reminders in the skill service code. Finally, a customer will receive a card through the Alexa app indicating the the reminder has been delivered.
After the reminder is created, and permitted, Alexa will barge into any interaction a customer may be having with Alexa. A tone will play at the reminder time. Next, the applicable reminder will play. To learn more, check out the API docs.