unity代码在Xcode上提示：A build only device cannot be used to run this target。

如果没有连接手机，则会有以上提示，可以先用仿真器搞定。

解决办法：

In Unity, you must click on Build Settings > Player Settings And in Inspector, choose settings for iOS> Other Settings > SDK Version and make sure "Simulator SDK" is selected.

Now in Xcode, it can be viewed in the iPhone Simulator.