This tutorial explores how to build an analytical application on top of Google BigQuery, a serverless data warehouse. It uses public datasets from BigQuery to visualize the impact of the COVID-19 pandemic on people's lives for every country in the world. The application is built using Cube, an open-source analytical API platform that provides a semantic layer, caching, and high-level identifiers to work with data. The tutorial covers creating an API over BigQuery, defining a data schema, exploring the data, building an analytical app, and understanding how the app retrieves data from the Cube API.