iPhone OS 4 will bring multitasking to the iPhone 3GS, but not iPhone 3G.
During a preview of iPhone OS 4, Steve Jobs revealed there'll be over 1,500 new APIs in iPhone OS 4, allowing developers to access built-in applications including Calendar, Photo Library and Quick Look.
Alongside that there'll be 100 new features, with the most significant being multitasking. Double clicking the Home button will bring up a dock along the bottom of the iPhone screen, with icons showing all the apps that are running.
"We weren't first to this party, but we're going to be the best," said Jobs, claiming the company had resisted implementing the feature because it destroyed battery life and made the iPhone feel sluggish.
To prevent this Apple claimed to have looked at "tens of thousands of apps" to discover which parts of them needed to be constantly running in the background. These were then distilled into a new framework that will be offered to developers, allowing apps to save their state and idle in the background not consuming any power, then restart instantly from wherever they left off.
Alongside multitasking, another tentpole feature being rolled out in iPhone OS 4 is folders. Dragging one app over another on the Home Screen will automatically add them to a folder named after the section of the iTunes App Store where it was purchased - though this can be changed. These folders will display mini icons of all the apps inside and can be locked to the dock.
As a sop to business users, iPhone OS 4 will also bring more sophisticated e-mail handling, supporting multiple Exchange accounts, a unified inbox and threaded conversations. Wireless app distribution also debuts, allowing IT managers to automatically update all their employees' iPhones with new apps, without anybody needing to plug their device in.
Perhaps the most low-key unveil of the night was for iBooks. The eBooks app is making its way to the iPhone, and will automatically sync with your iPad library - much as the Kindle app does.
As expected, Apple unveiled its iAd's platform, which will allow developers to embed advertising into their apps. The ads will be sold and hosted by Apple, which will take 40% of the revenues.
However, rather than just flashing banner ads - these ads are essentially apps within apps. In one demonstration Jobs showed an advert for Toy Story 3 offering wallpapers, trailers, location on local cinemas based on GPS data, and an interactive game.
Jobs dismissed the possibility of running Flash on the iPhone, claiming that ad agencies could implement any video they wanted within their ads, so long as it was based on HTML 5.
When quizzed on why Apple wouldn't allow unsigned apps on the iTunes App Store he was equally combative, claiming that: "You know, there's a porn store for Android. Anyone can download them. You can, your kids can. That's just not a place we want to go."
iPhone OS 4 will be released to iPhone and iPod touch owners this summer, though jobs warned that older devices such as the iPhone 3G and iPod touch second generation won't support all the features, including multitasking.http://www.techcentral.ie/article.aspx?id=14874&newsletter=139