Recent proliferation in disruptive technologies has opened up a new horizon for Internet of Vehicles (IoV). The success of IoV highly depends on the robustness of vehicular information system as a dispute among the service providers on data rights or any kind of security violation could disrupt the transport services altogether. In this work we propose a blockchain based novel architecture for vehicle authentication and privacy preservation with seamless access control for IoV. Proposed architecture is decentralized, robust and scalable. Along with privacy preserving authentication and conflict-free access-log maintenance, the proposed BlockAPP protocol also supports an optional traceability feature. Performance evaluation using smart contact over Ethereum Blockchain validates the effectiveness of the proposed architecture. © 2018 IEEE.