Dev Days 2009 - iPhone Development Overview

Develop for iPhone
and Get Rich
(development experiences...)

DevDays October 2009 - Dan Pilone

Copyright 2009 Dan Pilone / dan@pilone.org / DevDays
Wednesday, December 23, 2009

The Plan

• Why do you want to develop for iPhone?
• The iPhone Ecosystem
• Tools and Technologies
• Approval and Sales


Results not typical.
Your actual income may vary. High returns
represent a relatively small percentage of
applications in the iTunes App Store. The App
Store is designed for maximum turnover of
applications. Placement in top 100 lists
dramatically inﬂuence sales. Placement above
50 typically double sales. Placement in top 10
increase sales by order of magnitude.


App Store Statistics


• > $1 Billion industry => $4B in 2012


• > 2 Billion downloads


• > 100,000 apps


• > 100,000 apps
• > 75% are paid apps


• > 100,000 apps
• Of the 20 categories in App Store, Games &
Entertainment represent 35%


• > 100,000 apps
• Of the 20 categories in App Store, Games &
Entertainment represent 35%
• Social networking, Photography, Finance, Medical
and Weather combined are 6.2%


Why are people
developing for iPhone?


Why is iPhone
successful?


Why is iPhone
successful?
• Development experience (Frameworks, UI,
tools etc.)


Why is iPhone
successful?
tools etc.)
• Approval Process


Why is iPhone
successful?
tools etc.)
• Makes Money for developers


Why is iPhone
successful?
tools etc.)
• Fantastic distribution mechanism


Why is iPhone
successful?
tools etc.)
• Fantastic distribution mechanism
• User Experience

UI Matters


Classics

Downloads to date: 450,000
Price: $2.99
Approx Income: $940,000


I Am T-Pain

Downloads to date: 300,000
Price: $2.99


Flight Control Downloads to date: 700,000
Price: $0.99


There is money to be
EARNED.


iPhone App Basics


You Need an Intel-based Mac

And the Apple SDK

Devices are optional

iPhone App Rules


iPhone App Rules

• No 3rd party background apps


iPhone App Rules

• Limited resources


iPhone App Rules

• Live in a sand box


iPhone App Rules

• Live in a sand box
• Must use published API


Designing a Traditional
App


is NOT
the same
as


iPhone Apps Are View Based

Frameworks and Tools


Framework Patterns

View
View
Controller

Behind the Scenes

#import <UIKit/UIKit.h>

@interface HelloWorldViewController :
UIViewController {

}

@end

Objective-C classes and Nibs built with
UIKit Interface Builder

Xcode


Full Featured IDE

Graphical debugger

Built in App Templates

Data modeler

Static Code Analyzer

Objective-C


C-based Language
! BOOL wasItZero;
!
! if (x == 0) {
! ! NSLog(@"Wow, x was 0.");
! ! wasItZero = YES;
! } else if (x == 1) {
! ! NSLog(@"You'd never guess. it was 1.");
! ! wasItZero = NO;
! }
!
! return wasItZero;


And then it goes off the
rails...
- (id)initWithNibName:(NSString *)nibNameOrNil
bundle:(NSBundle *)nibBundleOrNil {

if (self = [super initWithNibName:nibNameOrNil
bundle:nibBundleOrNil]) {
// Custom initialization
}

return self;
}


Objective-C means
message passing

[window addSubview:viewController.view];

receiver message argument


Messages are turned
into method calls
@interface UIView : UIResponder<NSCoding>
{
...
}

- (void)addSubview:(UIView *)view;

@end


Properties and Fields
@interface HelloWorldAppDelegate : NSObject
<UIApplicationDelegate> {
UIWindow *window;
HelloWorldViewController *viewController;
}

@property (nonatomic, retain) UIWindow *window;
@property (nonatomic, retain) HelloWorldViewController
*viewController;

@end


Properties and Fields
@interface HelloWorldAppDelegate : NSObject
<UIApplicationDelegate> {
UIWindow *window;
HelloWorldViewController *viewController;
}

@property (nonatomic, retain) UIWindow *window;
@property (nonatomic, retain) HelloWorldViewController
*viewController;

@end

@synthesize window;
@synthesize viewController;


Memory management??


Objective-C uses reference
counting

Memory management
is critical
- (void)dealloc {
[viewController release];
[window release];
[super dealloc];
}


The SDK includes
Instruments


Behind the Scenes

View
View
Controller

Behind the Scenes


UIViewController {

}

@end

Objective-C classes and
UIKit Views and Nibs

Interface Builder



UIViewController {

}

@end

UIView
UIView
Controller


UIViewController {

}

- (IBAction) tapMeButtonPressed: (id) sender;

@end

- (IBAction) tapMeButtonPressed: (id) sender {
! UIAlertView *alertView =
[[UIAlertView alloc]
initWithTitle:@"Tapped!"
message:@"Fingers of steel!"
delegate:nil cancelButtonTitle:@"Bo-ya"
otherButtonTitles:nil];

! [alertView show];
! [alertView release];
}


But what about
interacting with the UI?



UIViewController {
! UILabel *helloLabel;
}

@property (nonatomic, retain) IBOutlet UILabel
*helloLabel;

- (IBAction) tapMeButtonPressed: (id) sender;

@end

- (IBAction) tapMeButtonPressed: (id) sender {
! self.helloLabel.text = @"Fingers of steel!";
}


Breathe


Testing your code


iPhone Simulator


Simulator Issues

• No camera
• Single GPS (Core Location) point
• Limited gesture and accelerometer support
• Inﬁnite memory and performance
• Lax enforcement of permissions


But it’s worse than just
the simulator...


the simulator...

iPhone 2G
No GPS


the simulator...

iPhone 2G iPhone 3G
No GPS No Compass
No Video

the simulator...

iPhone 2G iPhone 3G iPhone 3GS
No GPS No Compass New OpenGL
No Video Better Camera
Quicker

the simulator...

iPhone 2G iPhone 3G iPhone 3GS iPod Touch 1G
No GPS No Compass New OpenGL No Cellular
No Video Better Camera No Ext.
Quicker Speaker

the simulator...

iPhone 2G iPhone 3G iPhone 3GS iPod Touch 1G iPod Touch 2G
No GPS No Compass New OpenGL No Cellular No Camera
Quicker Speaker

the simulator...

iPhone 2G iPhone 3G iPhone 3GS iPod Touch 1G iPod Touch 2G
No GPS No Compass New OpenGL No Cellular No Camera
Quicker Speaker yet...

You need to test on
real devices.


You are here

• You’ve written an app
• You’ve debugged it in the simulator
• You’ve installed it on a real device*

*...and it works

The App Approval
Process


It’s not as bad as
you’ve heard.


It will take two weeks
to be rejected*

*...or accepted.

They do test your app.


They will eventually
catch HIG or License
Violations.


Real World Example


Selling your app and post
approval


Analytics


Really hard to make
money with Ad based
apps


Localization


Two sales models


Chart Likage

100

75

50

25

0
People who like charts


Distimo Sept 09

Omnifocus

Downloads to date: >50,000
Price: $19.99


Wrap up

• Why do you want to develop for iPhone?
• The iPhone Ecosystem
• Tools and Technologies
• Approval and Sales


More
Information
Dan Pilone
Twitter: @danpilone
dan@pilone.org

iPhone Dev Site:
http://developer.apple.com/iphone


Q&A


Dev Days 2009 - iPhone Development Overview

More Related Content

Similar to Dev Days 2009 - iPhone Development Overview (20)

More from Dan Pilone (6)

Recently uploaded (20)

Dev Days 2009 - iPhone Development Overview