David Wolber, Hal Abelson, Ellen Spertus, and Liz Looney, App Inventor: Create Your Own Android Apps, available online at: http://www.appinventor.org/projects.
Portions of this workbook are from “Computing Science: Mobile App Development – Learner Support”, which may be found at: https://www.education.gov.scot/nationalqualifications/Documents/MobileAppDevelopmentLearner.doc.
The above resource is available through an Open Government License: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/2/.