Real-world testing gets IoT developers out of the ideal conditions of a test lab and into the world where customers use their products. Testing in the real world often uncovers unexpected errors not seen in the lab and helps developers harden their devices. Hardening connected devices by testing them in the real world is an IoT development and delivery best practice. This report is one of a series of best practices for building and deploying smart products to the internet of things (IoT).