Set up NTP server on iOS device
I'll quote two answers from Stack Overflow with the hope that it will help you figure out what you're trying to do.



There's a small iOS library named ios-ntp. I have used it in one project in the past and it seemed to work reasonably well.

As of mid 2013 the original ios-ntp project has a few missing pieces, so I have mirrored the original svn repository to github. You can checkout out a working version of the code here: https://github.com/jessedc/iOS-ntp

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If you're not developing a commercial application, peek at the linux source.

http://packages.ubuntu.com/source/lucid/ntp

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