MobilityTestbed, formerly known as DARP Simulation Testbed, is an open source, interaction-rich Multi-agent simulation model designed to test and evaluate various Dial-a-ride problem algorithms or other central or decentralized coordination or Resource allocation mechanisms within on-demand transportation systems. The testbed is built on top of the AgentPolis platform and employs a discrete event simulation paradigm. MobilityTestbed is developed by the Agent Technology Center at the Czech Technical University in Prague and released under the GNU General Public License v2.