Due to the growth of intelligent and self-driving vehicles, there are a multitude of data-driven applications such as user monitoring or traffic modeling and control. Each application often uses its own data-collection platform, leading to a scattered landscape of solutions for vehicular data-driven research and app development. We propose CarLab, a flexible and open vehicular data-collection platform which unifies this landscape of vehicular data-driven research and app development. In this paper, we survey the field of vehicular data collection, describe the system architecture of CarLab and related research issues.