They essentially act as regexes that when match allow for an external application to be called with that text sent as a parameter. This allows for dates to be clickable and create and event in a calendar for example.
They also do a good job of taking phone numbers from emails and when an unknown call comes in suggesting that it might be the person who included that in an email.
These features generally work well in their apps, but I think there's less support for third parties to create custom options (though I haven't actually tried so not sure).
https://developer.apple.com/reference/foundation/nsdatadetec...
They essentially act as regexes that when match allow for an external application to be called with that text sent as a parameter. This allows for dates to be clickable and create and event in a calendar for example.
They also do a good job of taking phone numbers from emails and when an unknown call comes in suggesting that it might be the person who included that in an email.
These features generally work well in their apps, but I think there's less support for third parties to create custom options (though I haven't actually tried so not sure).