The hacker group known as iPhone Dev-Team apparently is close to unlocking iPhone 4 in order to run unofficial apps and to use other GSM cellular networks. Unlocking the operating system, usually termed jailbreaking, lets the user further customise the phone and load and run applications apart from Apple's iTunes/App Store website.
Unlocking the cellular baseband, sometimes called either a carrier unlock or a SIM (Subscriber Identity Module) unlock, means the phone can accept a different SIM card to work on other GSM networks.
Wikipedia has an exhaustive account of iPhone/iOS jailbreaking attempts and tools. Some bloggers, such as Mic Wright at ElectricPic.com, are already making their wish lists of jailbroken applications, which need a custom installer such as Cydia. Wright listed five:
- Allowing Apple's FaceTime video chat to work on 3G cellular connections.
- Support for 720p high definition video uploads, not just downloads.
- Installing custom wallpapers and themes, changing iPhone icons, and so on, similar to the capabilities in Winterboard (iPhoneHeat.com has a Winterboard tutorial).
- And an application to turn the iPhone 4 WiFi adapter into a local hotspot, letting other devices attach to the iPhone and share its 3G connection to the Internet.
- Wireless gaming controller to work with the Wii, Xbox 360 or PS3, exploiting the iPhone 4's new gyroscope.
Early on July 5, one of the developers, Planetbeing tweeted (@planetbeing) that he had accessed the baseband bootrom: "The baseband bootrom: c43b30a4ae92571338d93cc42c4050a40dce1e2a. However, @musclenerd and I have run into a speed-bump." A little later MuscleNerd tweeted: "Now that we have iPhone4 baseband bootrom, we can compare it to earlier 3G/3GS bootroms to see if any bug-fixes pop out."
Apple's iOS4 is a major upgrade, including a new baseband, as CNET.com noted. To complete the carrier unlock, the team has to rewrite the baseband code.
Apple has apparently included new code to frustrate the efforts of unlockers and jailbreakers. On July 4, Planetbeing tweeted: "Apple added an anti-blacksn0w trick this time around. ;) i have an ever-growing bag of tricks though, wrapped in a nice python script."
Blacksn0w is an unlocking application for iPhone 3G and 3GS, created by George Hotz, known as GeoHot. It was released in fall 2009, able to unlock the then-latest version of the baseband. It was subsequently included in Hotz's blackra1n jailbreaking application. Hotz himself apparently is not working on a iOS4 jailbreak application. In response to speculative tweet by a third Dev-Team member, @comex, @geohot tweeted: "@comex not sure why you wrote I am about to release. like you, I don't even own an iphone 4."
According to MuscleNerd, in a July 6 tweet, Comex is advancing a jailbreak similar to his Spirit application: "the next jailbreak from @comex is like first Spirit... all devices, all bootroms, latest FW, painless install." Spirit was released in March 2010, allowing a user to jailbreak a wide range of iOS 3-based devices, including the new iPad tablet. One big change, according to the Wikipedia entry, is that the iOS device no longer must be plugged into ("tethered") to a computer.
The Dev-Team has already released a jailbreaking tool, PwnageTool 4.01, for iOS devices that can support iOS4 – iPhone 3G and 3GS, and iPod touch 2G. The application, which runs on Mac OS X, can create custom iOS firmware images.