<P> As mentioned above, one use of encryption in iOS is in the memory of the Secure Enclave . When a passcode is utilized on an iOS device, the contents of the device are encrypted . This is done by using a hardware AES 256 implementation that is very efficient because it is placed directly between the flash storage and RAM . </P> <P> The iOS keychain is a database of login information that can be shared across apps written by the same person or organization . This service is often used for storing passwords for web applications . </P> <P> Third - party applications such as those distributed through the App Store must be code signed with an Apple - issued certificate . This continues the chain of trust all the way from the Secure Boot process as mentioned above to the actions of the applications installed on the device by users . Applications are also sandboxed, meaning that they can only modify the data within their individual home directory unless explicitly given permission to do otherwise . For example, they cannot access data that is owned by other user - installed applications on the device . There is a very extensive set of privacy controls contained within iOS with options to control apps' ability to access a wide variety of permissions such as the camera, contacts, background app refresh, cellular data, and access to other data and services . Most of the code in iOS, including third - party applications, run as the "mobile" user which does not have root privileges . This ensures that system files and other iOS system resources remain hidden and inaccessible to user - installed applications . </P> <P> iOS supports TLS with both low - and high - level APIs for developers . By default, the App Transport Security framework requires that servers use at least TLS 1.2 . However, developers are free to override this framework and utilize their own methods of communicating over networks . When Wi - Fi is enabled, iOS uses a randomized MAC address so that devices cannot be tracked by anyone sniffing wireless traffic . </P>

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