Apple has warned developers to stop tracking people and their behavour.In a message to developers the US Company has warned them to stop using a software feature found in iPhones and iPads that has been linked to privacy concerns.

The Wall Street Journal said that according to observers developers who write programs for Apple’s iOS operating system have been using a unique identifier specific to each device to gather personal data about users, in some cases creating detailed dossiers on how they use multiple apps. 

But Apple advised developers not to use that ID number, known as UDID or Unique Device Identifier, with a new version of the operating system that is expected to become available in coming weeks.

The company set no specific deadline for the change. But it stated on a website for developers that the feature “has been superseded and may become unsupported in the future.” It said they could still create an identifier unique to each individual application, however.