2. How we can reproduce it using the example you attached
Problem1.
- Increase the FOV to 100 on the main camera
- Build targetting android
- Start the apk on your android
- Observe on the rocks the dotted result ( if you move the camera around in the editor, you might notice a dotted shadowy rectangle being cast onto the mesh which I have no idea where it's coming from, but realtiem shadows appear inside it, possibly a Unity optimization for the shadow engine? )

Additional Steps:
- Go back to the project and decrease the FOV on the main camera back to 60
- Deploy and observe that the shadow artifacts do not appear

tested here:

Version 5.3.4f1 (fdbb5133b820)
Thu, 10 Mar 2016 22:34:57 GMT
Branch: 5.3/release