Beer Paula - Hello App Inventor! : Android programming for kids and the rest of us

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Development editor: Susanna KlineCopyeditor: Tiffany TaylorProofreader: Alyson BrenerTechnical proofreader: Jerome BatonTypesetter: Marija TudorCover designer: Leslie Haimes

ISBN 9781617291432

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To anyone who really, really tries. Come on, keep going, youre nearly there.

P.B.

To Frank, who treated us like geniuses and loved us fiercely.

C.S.

We think writing computer programs is fun and that those who can do it can make a difference to the world around themsometimes in an almost magical way. But when you start out, its often hard to see how the programs you write can make any difference to anyonefor example, you might just be drawing simple shapes or adding up a bunch of numbers.

Back in 2012, we started using App Inventor with teachers and children and discovered it was a brilliant way to make computer programs that worked in the real world. Beginners could perform useful, imaginative, and fun tasks like a GPS treasure hunt or a homework excuse generator. The App Inventor books that helped us learn were great, but we wanted to focus on helping school-age kids and beginners become app creators. Paula proposed that we write a book, and within a day we had the original contents page and app list. This initial speed lulled Paula into a false sense of security, and colleagues now remind her that she waved her arms around and said Itll only take us 12 weeks! She was only off by a factor of 8 ...

But what a couple of years it has been! Throughout the book, weve woven in key facts and resources useful to beginning programmers and always tried to develop original (or inspired!) working examples. We feel that the power of visual programming languages is brought out through the concepts and the huge variety of apps that can be produced by users of the book. Our companion website provides great graphics and sounds for each of the apps and a really useful table layout so users can set up their designs quickly and get down to learning to program with App Inventor right away.

Weve used the resources from this book to teach App Inventor to primary-age kids, secondary-age kids, trainee teachers, experienced programmers, and experienced teachersand what we always see is fun, satisfaction, and engagement.

We hope you get a lot out of the book and make fun apps for you and your friends. Who knows? You might even make the next award-winning killer app!

Many people helped bring this book to fruitionmentors, colleagues, reviewers, editors, friends, and family. We thank you all.

Thanks to the reviewers who read the manuscript in various stages of its development and provided invaluable and encouraging feedback: Aditya Sharma, Alain Couniot, Andrei Bautu, Brent Stains, Chris Davis, Ezra Simeloff, Ian Stirk, John D. Lewis, Mark Elston, Michael Knoll, Phanindra V. Mankale, Richard Lebel, Rick Goff, and Ron Sher.

Thanks to the student reviewers from Avon Grove Charter School, West Grove, PA, whose comments helped make this a much better book for our target audience: Alex Wilson, Ian Khan, Jacob Snarr, Jake Kerstetter, James Cottle Vinson, Lewis Arscott, Rhys Cottle Vinson, and their teacher Jacqueline Wilson.

Thanks to Diane Blakeley and the brilliant pupils of Wellfield College for trying out the early chapters of this book and coming up with brilliant ideas for apps, especially the Homework Excuse Generator.

Thanks to the readers of Mannings Early Access Program (MEAP) for their comments and their corrections to our chapters as they were being written. You helped us to improve our manuscript.

Thanks to Shay Pokress at MIT for keeping us in the App Inventor loop. Thanks for your encouragement and also to the team at MIT who continue to support App Inventor as a great educational tool.

Our Manning editor, Susanna Kline, always made great suggestions and knew when to push and when to wait with patience and understanding while we grappled with difficult chapters; thanks for being a constant and encouraging presence.

Finally, thanks to the super-professional and efficient team at Manning who worked with us and supported us throughout: Marjan Bace, Scott Meyers (for taking a chance on us), Cynthia Kane, Candace Gillhoolley, Jerome Baton, Kevin Sullivan, Tiffany Taylor, Mary Piergies, and many others who helped along the way.

I would like to give huge thanks to my friends and family. In roughly how long I have known them order: my mum, Carol, who taught me the white-hot fear of not having a good book on the go; my dad, Bernie, who taught me how to teach using confidence-building examples; my brother, Andy Analogy Man, who taught me how to explain myself clearly; my sister, Netty, who taught me about priorities and how to juggle (career and family, not batons; she is rubbish at that); and my twin cousin Stephen and best chum Janet, who have always convincingly feigned interest in my progress and inspired me with their own achievements. Thanks to my in-laws, Gillian and John, and my friend Jeff whose own love of writing inspired me toward this possibility. To my Edge Hill colleagues Claire, Dawn, and Colette: your encouragement means so much.

To my coauthor and sparring partner Carl: its been fun, especially as I won the last round (dont you dare edit this out!). To my three delicious children, Sam, Ella, and Sophia: thanks for testing my apps, telling me when they were up to the mark, and making everything wonderful. Thank you for not spilling juice on my keyboard when occasionally I sat among you writing apps on treat night while watching Harry Hill. Finally, to my incredible husband Rufus: it is impossible to fail at anything with a man like you in my life.