Comment by rguldener

It varies a lot. Which is why we always recommend to start with the feature requirements/user problem and work backwards from there.

Examples: - Low latency to show X last emails a person had with a specific email address

- Enriching data from the emails/calendar with other data from your product (E.g. mapping email recipients to contacts)

- Knowing when a calendar event has changed (sometimes also possible with webhooks)

- Detecting deletes (maybe also possible with webhooks, not sure for gmail/calendar)