Preface

I’ve been involved in technology most of my life, and every year is more exciting for a technologist than the last. Innovations keep coming faster and faster, making it sometimes hard (and always expensive) to keep up. One of the most exciting innovations of the last decade has been the rise of the smartphone. The technology world changed the day Steve Jobs announced the iPhone, and it has been going from strength to strength ever since. I’ve been an avid iPhone user from the start, and I even wrote a couple of apps using Objective-C during the iPhone’s early years. The biggest thing I learned from that experience was that writing mobile apps is cool, but using Objective-C is painful.

Fast-forward a few years, and I was a bored C# developer. I’d been building trading systems for years, desktop apps designed to help other people make a lot of money with unexciting technology, and I needed a change. At the start of my career I was passionate about coding, writing code in my spare time and devouring books and training courses. After a number of years in finance, that passion was dying. I looked around for something to fire it back up, and I found the answer—Xamarin.

I’d spent years learning C#, and with Xamarin I could use those skills to build mobile apps for both iOS and Android. No longer would I have to write Objective-C code for iOS and Java code for Android. The world of mobile development had been opened up to developers like me using C#, a language I not only was very comfortable with, but also actively enjoyed using. I decided that Xamarin was the technology for me, bought myself a license, signed up for Xamarin University, quit my job, and spent four months in a co-working space learning Xamarin. I was hooked, and since then I haven’t looked back. I’ve been so passionate about the technology that I wanted to tell the world how easy it is to build cross-platform mobile apps.

One question that kept coming up in the community was, “How do I build a production-quality app?” There are many great guides on how to use the iOS and Android SDKs, but no end-to-end documentation on how to go from an idea to a working, tested, shipped app—documentation that takes advantage of design patterns like MVVM not only to build testable code, but also to take advantage of Xamarin’s most powerful capability: the ability to share large portions of your code between platforms. That was the inspiration for this book. Xamarin is a better way to write, test, monitor, and deploy mobile apps, and this book aims to show you how.