In addition to the standard transactional emails, we engaged our users with custom New York City content and feature emails spotlighting neighborhoods adjacent to their searches. Ongoing A/B testing steadily improved engagement rates.
User research suggested that renters didn't understand New York's apartment lottery system. So we I designed an MVP iOS app offering simple search/save/notification functionality. Although the app didn't leave Beta, the NYC Housing Development Corp. expressed interest in working with us to bring it to market.