Calendar APIs Startups

X.ai is an AI-powered personal assistant that schedules meetings via email on behalf of users. Founded by serial entrepreneur Dennis Mortensen after he sold his previous analytics company and discovered he had 1,019 meetings in a year (65% requiring rescheduling), X.ai has raised $44 million and uses a novel approach of testing market viability before building the full product—starting with a concierge MVP and only then raising seed funding to validate the technical approach through data labeling.