I have made a simple game using Unity with Vuforia and exported for Android and iOS. It works fine on Android, but on iOS it crashed and gave the error:
ArgumentNullException: Argument cannot be null. Parameter name: format at System.Type.GetTypeFromHandle (RuntimeTypeHandle handle) [0x00000] in :0 at System.String.FormatHelper (System.Text.StringBuilder result, IFormatProvider provider, System.String format, System.Object[] args) [0x00000] in :0 at System.String.Format (IFormatProvider provider, System.String format, System.Object[] args) [0x00000] in :0 at System.String.Format (System.String format, System.Object[] args) [0x00000] in :0 at UnityEngine.Debug.LogFormat (System.String format, System.Object[] args) [0x00000] in :0 at Vuforia.TrackerManager.InitTracker[T] () [0x00000] in :0 at Vuforia.TrackerManager.InitTracker[T] () [0x00000] in :0 at Vuforia.TrackerManager.InitTracker[T] () [0x00000] in :0
(Filename: currently not available on il2cpp Line: -1)