These are the standards that have been adopted and the challenges they’ve helped solve. You can comment on their effectiveness and implementation and read others peoples’ feedback.
Standard: RFC6350 vCard August 2011
Related challenge: Exchange of contact information
Standard: RFC5545 iCalendar September 2009
Related challenge: Exchange of calendar events
Standard: Common Alerting Protocol Version 1.2
Related challenge: Public emergency alert messaging
Related challenge: Sharing or collaborating with government documents