How to reproduce:
1. Open the project uploaded to owncloud or download Survival Shooter from Asset Store
2. Change platform to Android or iOS
3. In Preferences-> External Tools set Visual Studio as External Script Editor
4. In Player Settings make sure that Scripting Runtime Version is set to .NET 4.x Equivalent
5. In Build Settings enable Development build and Script Debugging
5. Build and run project on device (if it is iOS device, turn off XCode and play app in the device again)
6. While app is running, open script from project with Visual Studio
7. In Visual Studio attach Debugger to player (Run -> Attach to Process -> Unity Player Android Player or Unity Player iPhone Player)
8. Add some breakpoints,
9. Create few Watch variables, add breakpoint on few places where those variables change value
10. Start debugging and continue clicking "Continue execution" button in Visual Studio when it reaches any breakpoint
Result: after a while app crashes (5min not longer)

Reproducible: 2018.2.2f0 (app crashes after attaching to process), 2018.3.0a5, 2018.3.0a7

Tested on: Macbook Pro MacOS 10.13.6
Used devices: iPhone 8 plus iOS 11.0, Samsung Galaxy S9 Android 8.0.0
Also tried on Editor but it didn't crash