Unlit/Transparent is best choice?

Hello, I’m trying to make 2d game with unity for iOs. I’m mostly using Unlit/Transparent in scene to make parallax planes etc. But I realised transparent shaders have some overhead on iOs.
So I’m wondering, since I should use transparent shader, Is Unlit/Transparent is the best choice for mobile ? Because it’s not in the Mobile/ shaders directory. If more optimized shader could be made, how can I make them? Or are there any outthere.

Thank you…

Multiplying by a color doesn’t actually make any performance difference, so that shader is overly feature-poor. Also, it’s not in GLSL, which means performance will suffer. This is better:

http://forum.unity3d.com/threads/115455-Unlit-with-adjustable-Alpha