Beginning Mobile Application Development in the Cloud

Richard Rodger is the CTO of FeedHenry Ltd, a company specializing in bringing the first tools to develop cloud based applications for mobile devices. He is currently a member of the W3C Web Applications Working Group, which defines the standard for mobile widget applications. Wrox Beginning guides are crafted to make learning programming languages and technologies easier than you think, providing a structured, tutorial format that will guide you through all the techniques involved.

Introduction xxi

Chapter 1: Introducing Cloud-Based Mobile Apps 1

How to Build Mobile Apps in the Cloud 2

Using Your Existing Skill Set 2

Determining What Tools You Need 3

The Skills You’ll Learn 4

Two Big Ideas About the App Industry 4

Web Apps and the Future 5

The Cloud as the Future 6

Getting Started 7

Using JavaScript Functions 7

The WebKit Browser Engine 20

A Colorful Little App 21

Introducing the nginx Web Server 25

Summary 29

Chapter 2: Mobilizing Your App 31

Building a Touch-Sensitive Drawing App 32

How to Draw on the Screen 32

Drawing in Response to Touch Events 39

Applying the DRY Principle to Your Code 46

Using the Amazon Cloud 52

How Geography Affects Amazon AWS 54

Using the Elastic Compute Cloud 54

Deploying Your Mobile Web App 61

Deploying Your Mobile App to the Instance 65

Summary 67

Chapter 3: Building Mobile Web Apps 71

What You Can Do with Mobile Web Apps 71

Locating Your User 72

Responding to Device Orientation 74

More Features for Later 76

Installing Mobile Web Apps on iPhone Devices 76

Installing Mobile Web Apps on Android Devices 77

Introducing jQuery and jQuery Mobile 78

The jQuery Library 78

The jQuery Mobile Library 83

Building a To-Do List App 91

Summary 108

Chapter 4: Enhancing Your App 111

Using App Caching 112

Handling Touch Events 115

Touch Events 116

Gesture Events 118

Embedding an Interactive Map 127

The Google Maps API 127

Providing an Application Icon and a Startup Screen 131

Summary 132

Chapter 5: Building Apps In The Cloud 135

Server-Side JavaScript 136

Introducing Node 136

Installing Node 138

Using the Node Package Manager 141

Introducing the MongoDB Database 144

Cloud Analytics for Your To-Do List App 150

Doing the Math 150

Organizing Your System 152

Collecting the Usage Data 160

Submitting the Usage Data 164

Charting the Usage Data 167

Summary 174

Chapter 6: Use the Cloud! 177

The Classic Cloud Architecture 177

The REST Approach 178

Cloud Databases 179

Introducing Amazon SimpleDB 180

The SimpleDB Approach to Cloud Storage 180

The SimpleDB API 181

Putting the To-Do List App in the Cloud 182

Introducing the simpledb Library 182

Building a Command-Line Client 188

Working on Cloud Time 196

Running a Cloud Server 198

Synchronizing with the Cloud 203

Summary 209

Chapter 7: Enhancing the User Experience 211

Creating a Classic Tab Bar Interface 211

Implementing the jQuery Mobile Solution 212

Using the iScroll Solution 216

Enabling Mobile Audio and Video 222

Playing Audio in Your App 222

Playing Video in Your App 226

Launching Apps from Your App 230

Launching a Web Browser from Your App 230

Launching a Phone from Your App 230

Launching SMS from Your App 230

Launching Mail from Your App 231

Launching Maps from Your App 231

Launching YouTube from Your App 231

Summary 232

Chapter 8: Working With the Cloud 235

Storing Content in Amazon S3 236

The Architecture of Amazon S3 236

Using Amazon S3 238

Signing In with the Cloud 247

Building Large-Scale Apps 255

Getting the Big Picture Right 256

Using the Cache! 258

Summary 271

Chapter 9: Creating Hybrid Apps That Run Natively 273

Introducing Hybrid Apps 274

The PhoneGap Project 274

Building Hybrid Apps 275

Building an iPhone App 275

Understanding Code-Signing 276

Building an Android App 283

Using Device Features 288

Lifestream, a Photo-Blogging App 294

Uploading Pictures 295

Storing Pictures on Amazon S3 306

Summary 310

Chapter 10: Building a Photo-Blogging App 315

The Architecture of Lifestream 316

Building the Server 317

Laying the Foundation 317

Enabling User Following 333

Uploading and Posting Pictures 336

Completing the Lifestream App 345

Supporting User Accounts 346

Integrating Social Network Identity 357

Summary 368

Chapter 11: Working With Cloud Development Services 371

Getting to Know the Mobile App Development Platforms 372

Using the FeedHenry Platform 373

FeedHenry Technology 374

The FeedHenry Development Environment 375

Deciding to Use FeedHenry 376

Using the Appcelerator Platform 377

Appcelerator Technology 378

The Appcelerator Development Environment 379

Deciding to Use Appcelerator 380

Using the appMobi Platform 381

appMobi Technology 382

The appMobi Development Environment 383

Deciding to Use appMobi 384

Summary 384

Chapter 12: Going Social! 387

Using the Twitter API 388

Working with the Twitter API Usage Limits 390

Using the Entities that the Twitter API Exposes 390

The Parts You Need 391

An App for Direct Messages 395

The Design Process 395

Getting the Hygiene Factors Right 399

The Code Structure 404

OAuth Without a Server 413

Calling the Twitter API 421

Event Consumers and Producers 425

Summary 431

Chapter 13: App Stores 435

What You Need to Publish Your App 436

Icons 436

Splash Screen 438

Screenshots and Orientations 439

App Metadata 440

Working with the App Stores 440

Building Your App for Release 441

Summary 452

Chapter 14: Selling Your App 455

Determining a Marketing Strategy 456

Building Apps for Others 457

Using Apps to Promote Your Business 458

Selling Your Own Apps 460

Choosing Tactics for Promoting Your App 462

Standard Tactics 463

Expensive Tactics 465

Guerrilla Tactics 466

Summary 468

Appendix: Exercise Solutions 471

Index 505