This is the first lesson in the ‘App Inventor’ scheme of work. This lesson is aimed at giving learners an introduction to app development and within this lesson learners will have scope to build their first app. All lessons within the scheme are targetted at KS3/KS4 and appropriately mapped to elements of the Computer Science 9-1 GCSE. Each slide includes detailed notes to support teacher understanding and have been based on a lesson plan structure. There is no prior knowledge required from the class teacher. Using the ‘App Inventor’ emulator or a mobile device with the 'MIT App Inventor app ’ installed will allow learners to practically use the apps they build. The app can be downloaded freely from the ‘Google Play’ store.