Vehicle access control and in particular access to in-vehicle functionalities from smart mobile devices, e.g., phones or watches, has become an increasingly relevant topic. Security plays a critical part, due to both a long history of car keys that succumbed to attacks and recently reported intrusions that use various vehicle communication interfaces to further gain access to in-vehicle safety-critical components. In this work we discuss existing technologies and functionalities that should be embedded in an experimental setup that addresses such a scenario. We make emphasis on existing cryptographic technologies, from symmetric to asymmetric primitives, identity-based cryptography and group signatures. We also discuss risks associated with in-vehicle functionalities and mitigation, e.g., intrusion detection systems.