Due to the policy of Apple, users will see the reminder of “Untrusted Corporate Developer” when they are installing the corporate version application for the first time.
The solution (With IOS11 system as an example)：
1.Open the settings in your phone and choose “General”;
2.Then choose “Profiles & Device Management”;
3.Check the category of corporate application types and choose the name of corporate application about to be installed. (which should be consistent with that of the reminder) Then click and enter;
4.After entering into the webpage of corporate signature, confirm again the name of corporate and application and then click “Trust”;
5.Go back to the desktop and re-open the application.