Connected vehicles provide suppliers and OEMs new opportunities to improve their customer experience and offer new services. Yet, in this new era of Internet of Things (IoT), OEMs and suppliers are expected to expand their engineering efforts beyond the vehicle itself. We present a new Rapid Application Development (RAD) service offered by IBM, called IBM Internet of Things Workbench. This is a visual tool, offered as an IBM Bluemix service that allows engineers to design and simulate the overall architecture and interactions between the various IoT entities such as devices, cloud applications and services, mobile clients and asset management systems. IoT Workbench abstracts the messaging details and generates code skeletons for the cloud applications as well as for simulating devices. It also provides the device simulation to allow for the application testing before the actual devices are available and the requirements for the various devices are validated. This service is unique from other IoT offerings in the sense that it focuses on the design domain rather than being an operational service, while on the other hand it is focused on the operational environment as opposed to generic design tools that need to be adapted for specific domains.