Glow/Spotlight shader not working on OSX/Android/iOS (OpenGL)

I'm working on a project where we use a shader that creates a spotlight/cameralight effect. This effect doesn't seem to work on OSX/Android/iOS and I can't seem to find the reason for that, but it's probably something with OpenGL because when I add

"#pragma only_renderers openGL gles gles3"

the materials become pink and the shader says that it either has errors or that it is not supported.

I want this shader to work on all platforms, not only on Windows.
Could someone please help me on this issue. Pictures and code are posted below.

Code (CSharp):

1. Shader "Custom/GlowLine" {
2.   Properties {
3.       _TintColor ("Tint Color", Color) = (0.5,0.5,0.5,0.5)
4.       _MainTex ("Particle Texture", 2D) = "white" {}
5.       _BrightnessFactor ("Brightness Factor", Float ) = 1.0
6.       _BrightnessHardness( "Brightness Hardness", Float ) = 2.0
7.       _LineHardness( "Line Hardness", Float ) = 2.0
8.   }
9.  
10.   Category {
11.       Tags { "Queue"="Overlay" "IgnoreProjector"="True" "RenderType"="Transparent" }
12.       Blend SrcAlpha One
13.       ZTest Always
14.       AlphaTest Greater .01
15.       ColorMask RGB
16.       Cull Back Lighting Off ZWrite On Fog { Color (0,0,0,0) }
17.       BindChannels {
18.           Bind "Color", color
19.           Bind "Vertex", vertex
20.           Bind "TexCoord", texcoord
21.       }
22.      
23.       // ---- Fragment program cards
24.       SubShader {
25.           Pass {
26.          
27.               CGPROGRAM
28.               #pragma vertex vert
29.               #pragma fragment frag
30.  
31.               #include "UnityCG.cginc"
32.  
33.               sampler2D _MainTex;
34.               fixed4 _TintColor;
35.               float _BrightnessFactor;
36.               float _BrightnessHardness;
37.               float _LineHardness;
38.              
39.               struct appdata_t {
40.                   float4 vertex : POSITION;
41.                   fixed4 color : COLOR;
42.                   float2 texcoord : TEXCOORD0;
43.               };
44.  
45.               struct v2f {
46.                   float4 vertex : POSITION;
47.                   fixed4 color : COLOR;
48.                   float2 texcoord : TEXCOORD0;
49.                   float4 position : TEXCOORD1;
50.               };
51.              
52.               float4 _MainTex_ST;
53.  
54.               v2f vert( appdata_t v )
55.               {
56.                   v2f o;
57.                   o.vertex = mul( UNITY_MATRIX_MVP, v.vertex );
58.                   o.color = v.color;
59.                   o.texcoord = TRANSFORM_TEX( v.texcoord,_MainTex );
60.                   o.position = o.vertex;
61.                   return o;
62.               }
63.  
64.               sampler2D _CameraDepthTexture;
65.              
66.               fixed4 frag( v2f IN ) : COLOR
67.               {
68.                   half4 texColor = pow(tex2D( _MainTex, IN.texcoord ), _LineHardness );
69.                   float brightness = 1.0f / pow(dot( IN.position, IN.position ), _BrightnessHardness) * texColor.a;
70.                   return 2.0f * (IN.color )* _TintColor * texColor + (brightness * _BrightnessFactor) * 0.1f;
71.               }
72.               ENDCG
73.           }
74.       }    
75.   }
76.   }

 

I figured out the shader DOES work on Mac but it reacts different. The alpha stuff works fine but the lighting reacts way different on Mac than on Windows.