14 DAY TRIAL // Apple is on track to release iOS 4 for compatible devices today, according to a generally reliable source of such type of information. Softpedia believes the story may be accurate, not because the launch date would be in line with previous releases (as the source erroneously outlines), but because iOS 4 has long been promoted to GM status, and is well supported on existing devices.
According to a website focused on Apple-related matters, Apple has previously labelled June 21 as the launch day for its next major OS upgrade for iPhones and iPod touches. While there is a basis to this assertion, the fact that 10am Pacific would be in line with previous releases does not sound quite as accurate. Nevertheless, iOS 4 is known to be ready, from a functional point of view, to be downloaded and installed on iPhones and iPod touches that have the appropriate specs to boot it.
Supported devices, according to Apple, include iPhone 3G, iPhone 3GS, second- and third-generation iPod touch late 2009 models with 32GB or 64GB, and, of course, the iPhone 4. In Fall, Apple plans to roll out an iPad-specific version of the software. However, even supported devices will have a hard time handling some iOS 4-specific features. A good example is the rather old iPhone 3G, which doesn't boast enough RAM to handle multitasking.
Unlike previous major iOS releases, Apple is allowing everyone to upgrade for free this time around, including iPod touch owners. Until now, Apple has charged iPod touch owners either $10 or $5 for their software updates (depending on how major of an update it was). iOS 4, as confirmed by Apple’s CEO himself, is a free upgrade for everyone who owns a supported device.
iPhone and iPod touch updates are provided by Apple via iTunes, the company’s proprietary digital media player application that also acts as the browser for its iTunes Stores, including the App Store and iBookstore. iPhone OS / iOS software updates arrive in the form of a software bundle bearing the .ipsw extension. Customers need to connect their devices to their computers and use iTunes in order to perform the tethered installation of the new software.
UPDATE: the iOS 4 software update is now available for all supported devices (excepting iPad).