Having developers on a company's side has long been a competitive advantage in the technology industry. Microsoft found that in the 1980s and 1990s when many programmers created for Windows and shunned Apple's Macintosh operating system for personal computers.
Microsoft has since seen the flipside, with fewer developers making apps for its Windows Phone software. That has left Windows Phone-based hardware trailing Apple's mobile devices and Google Android gadgets.
Apple worked to make it clear on Monday that it isn't taking developers for granted. The company started its event in San Francisco with a video praising the crowd of 6,000 developers, who cheered wildly at nearly every new feature showed by Apple executives.
"From all of Apple, thank you very much," Cook said during the keynote. The announcements are meant to help build apps on a "whole new level," he said.
Watch: Apple updates OSX, IOS
Competition for developers in the $23 billion apps industry has intensified in the past few years as more companies strive to grab a piece of the mobile market. Google, which is holding its own developer conference in San Francisco later this month, has overhauled its Google Play apps store to make it more customer friendly and added tools to simplify the production of apps for Android devices.
Facebook also introduced its own set of software tools last month so makers of mobile apps would use its servers as a foundation for producing its programs.
The threat is clear for Apple. As of the end of last year, Android's worldwide market share was 78 per cent, up from 66 per cent in 2012, according to researcher Gartner. Apple's mobile software, iOS, had a 16 per cent share last year, down from 19 per cent in 2012.
The market shifts were enough to push startup WhoDoYou to begin its service on Android instead of the iPhone platform. The business recommendation service, which competes against Yelp and Angie's List, debuted earlier this year.
"We track the percentage of mobile users very carefully and have found that Android is growing more quickly than iPhone," CEO Yoav Schwartz wrote in an e-mail. "Our iPhone app will be coming out soon, so it's not a very strategic decision, but we thought it made sense for us to start on Android first."
Apple still enjoys a key advantage over its rivals: money. Applications make about 85 per cent more revenue on Apple devices than they do on Android, according to App Annie, which tracks the market.
With its newest software unveiled on Monday, Apple added features to address criticism from developers who are finding it harder for their programs to be discovered and make money amid a sea of software.
Apple rolled out new search tools to help customers find programs to download, as well as app bundles so they can buy a batch of apps at a discounted price. The company also added a testing feature so app makers can get people to try something in development, and previews so users can view short videos to see if it's something they want to download.
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Apple also added ways for applications to work more closely with each other -- for example, a photo edited in one application can be quickly added to another one. The apps are currently isolated so data can't be shared with another tool.
Developers also will be able to take advantage of new software for health tracking and controlling home appliances. Apple debuted HealthKit to serve as a hub for the different programs now available that track fitness, including steps taken, food eaten or heart rate.
Apple also showed HomeKit, a set of tools for developers to make iPhones work with so-called smart homes by controlling things like a light bulb, door lock and garage door with a smartphone.
Another new feature allows coders to write programs that use Apple's TouchID fingerprint-authentication technology that's on the iPhone 5s. That had previously only been available for Apple services.
In addition to the developer announcements, Apple previewed new iPhone and iPad software, called iOS 8, and a redesigned Mac operating system, called Yosemite. Both will be released later this year.
The updates offer a glimpse of Apple's direction since the death of co-founder Steve Jobs in 2011. With iPhone and iPad sales no longer the source of growth they once were, Cook has been under pressure to deliver another hit. Last week, Eddy Cue, Apple's head of Internet services, said the company's product pipeline is the best it has been in 25 years.
The health-tracking software Apple unveiled on Monday is seen as Apple's first step toward introducing a wearable device later this year.
"It was a show for laying the foundation for the next structures that are going to be built," Horace Dediu, a mobile-industry analyst who runs Asymco, said at the conference.
- Bloomberg