Transit agencies collect a vast amount of data on vehicle positions, passenger loading and, increasingly, origin-destination flows. Collecting and synthesizing this data to support operations and planning is a significant challenge and can be constrained by information silos within transit agencies. In this paper, an open-source bus performance and journey visualization dashboard, Ridership and Operations Visualization Engine (ROVE), is presented that integrates multiple disparate data sources into a flexible and iterative analysis tool. It differs from existing commercial products by including origin-destination flows along with standard performance metrics, and is designed to be adaptable and relevant to any transit agency. Two case studies are presented to demonstrate the functionality of the dashboard: planning transit priority infrastructure and evaluating network design changes. The dashboard was developed in partnership with Chicago Transit Authority and Massachusetts Bay Transportation Authority, and practical details from the installation and maintenance procedures are included for prospective users.