New government rules announced on Monday will allow iPhone users to unlock, or "jailbreak," their phones without violating the law.
The amendments to the 1998 Digital Millennium Copyright Act will allow users to run third-party applications on their iPhones that have not been approved by Apple.
Apple had objected to the changes, stating that the running of unauthorised programmes on the popular mobile device could lead to potential problems with the smartphone. But the company will still be allowed to outlaw such actions on the terms of service agreements that users must sign when buying the phone.
The decision by the Copyright Office of the Library of Congress also allows consumers to unlock other mobile phones to run third party applications and to enable the devices to work with multiple carriers.
The Electronic Frontier Foundation, which pressed the Copyright Office to relax its rules on mobile phone use, welcomed the move saying that the new rulings take "unprecedented new strides towards protecting more consumers and artists."