The API we used: NSURL *url = [NSURL URLWithString:@"App-Prefs:INTERNET_TETHERING"];
The link provided by Apple engineer: https://developer.apple.com/forums/thread/761314
I did not find any URL in the link that leads to the secondary menu of system settings. Does this suggest that iOS 26 does not support this functionality? Moreover, is it possible that versions of iOS 18 and earlier may also not support this behavior in the future?
If you're reposting this because the comments on your original thread went unanswered, check out point 5 in Quinn’s Top Fourteen DevForums Tips: don't use the comment feature for followup discussion because people tend to miss them.
Does this suggest that iOS 26 does not support this functionality?
What's supported is what Apple documents. Any behaviors that aren't documented should be considered undefined and unsupported.
is it possible that versions of iOS 18 and earlier may also not support this behavior in the future?
Of course it’s hard to imagine Apple tasking some poor engineer with deliberately breaking this behavior in some future patch release. But IMHO a better way forward is to just update your app to give a consistent experience on all OS versions rather than trying to manage two paths, one of them being on a legacy OS whose user base shrinks every day.
