This document discusses building mobile backends. It outlines common roles of mobile backends, including statistics, user management, configurations, logging, push notifications and scoring. It then discusses using third party mobile backend as a service (MBaaS) solutions versus building your own custom backend. When building your own, it recommends technologies like Node.js, .NET, PHP, Java, databases like MySQL and MongoDB, and infrastructure like AWS, Google Cloud and Azure. It then provides an introduction to Node.js as a non-blocking and event-driven server-side JavaScript platform. Finally, it proposes a demo of creating a simple logging server in Node.js within 10 minutes.