Abstract: Edge intelligence, which comprises networking, computing, storage, and intelligence, pushes intelligence to the edge of the network and opens the way for low-latency critical computing in the Internet of Everything era. To further meet the critical needs of elastic connectivity, data optimization, real-time edge business processing, security, and privacy protection under the Internet of Everything, blockchain has great potential to accelerate edge intelligence. The integration of edge intelligence and blockchain has complementary advantages. In this context, we explore the relationship between edge intelligence and blockchain, introduce the most recent research, applications, and challenges in terms of blockchain-driven edge intelligence and edge intelligence-driven blockchain, and broaden the horizon for ubiquitous intelligent services.