This is an issue with large code bases which is answered by Unity in their troubleshooting guide: http://docs.unity3d.com/460/Documentation/Manual/TroubleShootingIPhone.html
Disabling script debugging in Player Settings will fix the issue. Alternatively you can cut down on project size by including the brainCloud library as a DLL. The gitHub repository includes Visual Studio and Mono projects to compile brainCloud as a DLL.
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