In my app I have a button to update the same app by ad hoc distribution. In that link I do the next action:
[[UIApplication sharedApplication] openURL:[NSURL URLWithString: @"itms-services://?action=download-manifest&url=http://url/manifest.plist"]];
So then it appears the alert message and I tap ok, and then the app is closed and it starts the installation.
the first question is: That´s this way the best way.
I´d like to manage the errors that it can happen, for example, It interrupts the connection.
Or if had an error, and it can not install the app, I´d like run the previous version.
Yes this is the best way and you can't check for error's.
iOS is handeling the download ans install of the new version and you can't access this process.