Android can be a lot of things depending on your point of view.
For Google, Android is a vehicle to expand their business into new areas where they were absent a few years ago. Google has evolved from a web search engine into a company with many product lines and businesses—from mobile phones, music, and books to video-on-demand. With the release of Android Lollipop, you can also add TV and wearables to that list.
For mobile manufacturers—such as Samsung, LG and HTC—Android is an Open Source mobile operating system (OS) they can tweak and use without paying royalties.1
For users, the Android OS is less visible but is nevertheless a critical piece of their daily activities. They depend on Android to send and receive emails, chat, take pictures, entertain, and much more. Average users are not power users, and as such they will want quality apps that will run without crashing.
For us as developers, Android is a way to express our creativity (outside of our 9–5 routine), learn mobile software development, and make some money on the side. Regardless of the reason that brings you to Android software development, you are (or will be) faced with the same problems that fellow Android developers encounter every day. These include: fragmentation, legacy code, bad code, ineffective monetization, and so forth. Most of these burdens can be avoided or mitigated by using the right tools and techniques combined with an agile mindset. These effective techniques and tools can help you enjoy Android programming even more by freeing up your time, so you can really develop—instead of just fixing problems, looking for answers on StackOverflow, avoiding pitfalls, or rewriting the same boiler plate code over and over again.2
By the end of this book, you should be a more productive and, therefore, happier Android software developer. You would be surprised what a happy developer can accomplish!
When I started learning Android programming, I sometimes found myself confronted by a daunting task and wondering, “Is there a more agile way to do this or that?” I’ve been searching for answers in Android programming books expecting to find something about the tools I use daily in my job but used in the context of mobile application development. Yet I have found nothing.
Why is that? There are a bunch of great tools out there that can make your Android software development experience more enjoyable. Many of these tools are free and Open Source, but they are not covered in any book. My theory is that most Android programming books are targeted at novices and seldom at intermediate-level Android developers (our audience here). I think you have to experience (and even suffer a bit) with Android app development before you start looking around for more agile, alternative ways of doing things.
In this book, we covering most of the tools normally described in Application Lifecycle Management (ALM) or DevOps3 books, but used in the context of Android software development. Think of DevOps for a team of one!
I also share my experiences about monetization, marketing and other things not related to Android programming per se, but essential to successfully publishing an app in Google Play or other Android app stores.
Because of the number of topics covered in this book, I will not throw a bunch of code in your face (lucky you). Instead, I’ve selected a simple example that we will use from the first chapters until the end of the book—the FizzBuzz app.4 The Fizz Buzz algorithm is great to teach developers how to do test-driven development (TDD), and it is simple enough to let us focus on the techniques rather than our problem-solving skills. We evolve this app from a wireframe concept on paper to a fully functioning app that we release to Google Play. All of the concepts demonstrated in this book are usable for other apps you develop. At the end of each chapter, there are some hints to guide you on how to use the concepts to your own benefit.
This book is targeted at experienced software developers who are familiar with at least one Object Oriented Programming (OOP) language, such as C++, C#, or Java. You should also have some basic understanding of source code control (preferably Git), shell scripting and Linux (if you know how to open a command shell, you will do great).
The techniques and tools shared in this book are presented mostly in the context of a team of one—that is, one indie developer who wants to take his Android development workflow to the next level. The concepts presented in this book can also apply to larger teams, but this is not our main audience.
To get the most from this book, you should already have read one or more entry-level books about Android programming (see the following Recommanded References section), and you should already have released one or more Android apps to Google Play.
This book does not cover Android basics, but it does its best to address all those questions you may end up with after we present advanced topics. In the case where some intermediate to advanced knowledge is required to fully understand a topic, you are provided with references to look up.
Additionally, if you have some experience with Agile software projects, this will give you a head start, but it is not required.
Finally, if you are an experienced developer working full-time for your boss’s software company—and dreaming of doing your own things—you will find food for thought in this book. Likewise, if you’re looking to improve your Android programming workflow, learn new tools and techniques, develop more agile apps—and even make some money with Android—this book is definitely for you!
Big disclaimer: This book is, at times, very opinionated. Mea culpae, the core of this book comes from my years on the IT battlefield, and I’ve learned the hard way what works and what doesn’t.
I beg you to differ and share your view about any subject covered in this book in the discussion group (see the following How to use this book section). For this book, I have positioned some tools that I find work great in the context of Android project development. They may not be the best tools on the market, but they are the best I have found to get the job done. (They also happen to be the tools I know and use every day). I will explain the process I use to select tools among many equivalents in the chapter on technological watch. You will be able to use these concepts beyond Android app development
I’ve developed the book examples on Linux and haven’t fully tested these on Windows or OSX. However, due to the portable nature of Android (and Java), they should work out-of-the-box on any platform. Generally, for the sake of agility, I do my best to select tools that are platform-independent or web-based. If some examples or scripts don’t work as expected in your development environment, I encourage you to submit a bug report to me with as much detail as possible (and if you happen to find a solution specific to a platform, send that as well). If I can help you, I will, or another reader might be able to give you a hand.
I designed the content of this book as a greenfield project (that is from scratch or without the legacy) and for a team of one or a “two-pizza team”5 in mind. At times, the tools and processes I present will seem like killing a fly with a bazooka if you’re a lone developer, but they will help you structure your work and keep you organized. In fact, if you end up growing your app business (and I hope you will!), you will be grateful that you have observed a Spartan discipline with your Android projects because the best practices already will be assimilated by you and your team, and they will serve as the cornerstone of your Android business.
All designs, processes, examples, concepts, and such presented in this book had to meet the following criteria before being included:
All of this was taken into account for the sake of helping you reduce the time-to-market for your apps and let you focus on developing great ones.
This book is organized in six parts:
In Part 1, we set up and present the tools I propose to fill your Agile Android developer toolbox. By the end of Part 1, you will have set up a development environment that will help you build our example application. In Part 2, building upon what we’ve learned in the previous chapters, I teach you how to optimize your development process by automating tedious or repetitive tasks, so we can concentrate on tasks with added value in building our final app. Then, in Part 3, we look at software management using Agile tools and methodology. We also talk about subjects like behavior-driven development (BDD) and TDD to help us document our code and designs. In Part 4, we locate and eliminate sources of waste. We follow some theories provided by the Lean Startup movement and learn how to implement an effective feedback loop (Build-Measure-Learn loop) for Android software projects. In Part 5, I show you how to use cloud computing to your advantage and scale your builds and tests to multiple environments. Finally, in Part 6, I talk about more advanced topics, such as marketing for your apps, publishing, and monetization tips and techniques.
In the appendix, I present less technical subjects that are usefull but not at the core of Agile Android software development. I present the techniques I use to monitor the evolution of the market, so I am alerted when new trends or opportunities surface. I also present how to select tools among equivalent alternatives.
I hope you enjoy the ride!
The first three parts of this book are meant to be followed in order like a tutorial. First, we put in place a development environment to support the Agile workflow we propose. Then, in the subsequent parts, we use that environment to build our example application and to improve it as we progress. You can always skip some content if you are already familiar with it. The Git repository is designed to provide you with the example app at a working state corresponding to a specific chapter. So you can pick it up from there and continue with more advanced topics without getting lost. If we think a chapter can be skipped by the more advanced readers (without impacting their comprehension of the following chapters), you will see an optional icon marking that chapter (see the following Conventions used in this book section).
The book was written with the idea of releasing it to the community in parts as it was written. That way, I was able to build a Build-Measure-Learn loop from the beginning à la Lean Startup.6 This book will continue to develop even after it is released, and it will be updated regularly using feedback from readers and by following the new trends the Android ecosystem brings us. So, as a complement to this book, I strongly encourage you to register—for free—to the following communities to stay informed of new events related to Agile Android Software Development:
You should also register for a free account on GitHub to access the Agile Android Software Development repository : https://github.com/Agile-Android-Software-Development. You will be able to get all the examples, scripts, and much more from the Git repository.
The following conventions are used in this book:
Constant width
Used for source code listings and reference of class, variable, parameter names, and such referring to code snippets.
Constant width in bold
Indicates source code that was modified to illustrate an improvement to a previously presented source code listing.
Italic
Used when referring to URLs, filenames, file extensions, and to put emphasis on technical terms the first time they are cited in a chapter.
This icon indicates a tip or a suggestion.
This icon represents a notice or warning.
This icon illustrates that a section of text can be skipped and is provided only to offer some depth to a topic but is not essential to its understanding.
If you need to deepen your knowledge or dust-off your Android programming skills, I recommend you the following books :
Étienne Savard is a dad, a certified Professional Scrum Master (PSM), a pragmatic programmer, and an Open Source advocate. He has been a software developer for a long time. It all started on a TRS-80 Color Computer (when 64K was a lot of memory and 16 colors were enough). Since then, he has continued to pursue his quest to boldly go where no developer has gone before!
Étienne works as an IT consultant helping companies (from startups to large corporations) integrate best-of-breed tools and best practices into their software development process, including most of the same tools and practices presented in this book.
He started Android programming with the Gingerbread version of Android by reading books, following tutorials, and looking at a lot of source code. Étienne has also released a couple of apps on Google Play with some success and a lot of trial and error. He enjoyed Android programming from the start because of its openness, community, and architecture. Etienne has found that the only missing part in the Android ecosystem is a more agile way of developing Android apps. This book is here to fill that gap.
If you omit the fact that Microsoft collected Android patent royalties from Android smartphone manufacturers. (http://www.businessinsider.com/microsoft-earns-2-billion-per-year-from-android-patent-royalties-2013-11)↩
My definition of boiler plate code is this: Any code that doesn’t add value to the final product. In our case, the product is an Android app. In Lean Startup terms, it’s synonymous to waste (waste of time, resources, money).↩
For details, see the DevOps definition on Wikipedia: http://en.wikipedia.org/wiki/DevOps↩
See the Fizz Buzz article on Wikipedia for details: http://en.wikipedia.org/wiki/Fizz_buzz↩
An expression coined by Jeff Bezos, CEO of Amazon. A small team (usually between 6 to 10 people) you can feed with two pizzas.↩