Loffing Cheyney - Beginning iOS Programming For Dummies

Beginning iOS Programming For Dummies

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Library of Congress Control Number: 2013954213

ISBN 978-1-118-79927--7 (pbk); ISBN 978-1-118-79931-4 (ebk); ISBN 978-1-118-79932-1 (ebk)

Manufactured in the United States of America

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Chapter 1

In This Chapter

Identifying the market

Following the design process

Entering the world of object-oriented development

Mobile devices are everywhere. These smartphones and tablets run powerful applications and are making a difference in how people live, work, and play.

Many folks already use these devices as they do computers: to create and edit documents; to interact with others via e-mail, telephone, and chat; to play highly entertaining games; and to shop and manage money. Even schools, which used to ban cellphones in the classroom, are considering delivering educational materials to students via smartphones. Because they're common and robust, tablets and smartphones are now the primary computing and communication devices for many people.

A mobile device, in particular a smartphone, is more than a computing and communication device, however. Because it goes everywhere with you, you can be constantly connected to work and with other users. Also, because a smartphone can retain information about people you talk to, where youve been, and how much you spend, it in a sense "knows" you intimately. Mobile applications can take advantage of this device-user relationship to provide personalized and targeted services that users will depend upon and love.

This book assumes that youve written applications for other platforms, such as desktop or laptop computers or the web. You can transfer a lot of this experience to writing applications for mobile devices like cellphones and tablets, including iOS devices.

However, when writing applications for iOS, you need to consider these differences:

• Tiny keyboards: iOS device keyboards make data entry very difficult. Data entry is no easy task to begin with, and touchscreen virtual keyboards, which you press with your thumbs, are prone to data-entry errors (for example, your app should provide smart spell-checking or allow the user to simply select from a set of options rather than making him type text).

  Some applications are created primarily to enter data (think Twitter or e-mail apps). However, try to limit data entry by doing things such as prefilling commonly used default values and providing drop-down lists that users can select from.

• Small display area: Displays on iOS devices come in these three shapes and sizes (see Figure ):
  • 4-inch iPhone and iPod Touch
  • 7.9-inch iPad mini
  • 9.7-inch iPad
    

    Figure 1-1: Here are the three iOS device sizes.

  Compare these sizes to laptop screens, which are usually 15 inches or larger, and youll see what I mean by limited screen space.

  In order to be usable on small screens, an application must be designed so as to allow users to

  • Move intuitively in the program (without getting confused by a maze of screens).
  • Use controls (buttons, for example) that are large enough to press easily and place them in a way that helps to prevent click errors.
• Universal applications needed: In order for an iOS application to be popular, it must run on a range of devices with varied capabilities that is, the iPhone, the iPad mini, and the 9.7-inch iPad (refer to Figure ).

  Applications need to function well on the smallest and largest iOS displays.

  Note that previous generations of iOS devices had even smaller screens (iPhones prior to iOS 5 and iPod Touches prior to the 5th generation all had 3.5-inch displays). Also, Apple TV runs iOS. If Apple opens these platforms for app development with the latest iOS versions, the problem of creating universal apps will become even more complicated.