Samsung Galaxy series device Problem of Unity3d Android Build

I am using Unity 3D is developing Android applications. This application is operating normally on the iPhone, iPod Touch However, while making the problem of the Android version occurred. After the build version of android, Was installed in the Galaxy series. (Galaxy S, Galaxy S2, Galaxy Note) After the application is running -> Running other applications -> Return to the first application -> Stop or kill the application(problem) However, the normal operation Motoroi(motorola) Is there a solution?

PS. This application is a 2d Game with EZGUI.