I believe I know what this issue is. The issue is that the C# bindings to the native methods need the following attribute added above, so this would include isUnderage: [return MarshalAs(UnmanagedType.I1)] The reason why you're seeing what you're seeing, is that bool is a 32-bit type in C#, while in C++ it's an 8-bit type. So the C# wrapper is reading another 24-bits of junk, which on the balance of probabilities, with return a true overall since there'll likely be a stray bit in the registers. This is a bug in the Apple Unity Plugins that impact any method that returns bool. It specifically only manifests on Intel chips.