Offset and Tiling Problem in Parallax

Hi everyone , i am making 2d parallax using Shader offset property of Texture and my code is given below.

renderer.material.mainTextureOffset = Vector2 (offset, 0);

it is working fine in unity Game layout after playing,and i am using texture in curve shape.but problem is when i run the build in iPhone the curvy shape of texture is showing in the square shape.I have changed the shader properties to a large extent to resolve the issue but still do not know ,why is it happening so.

i have attached the screen shot of both Scene.

[1]: /storage/temp/33773-iphone_screen.png