Lower Draw Calls For Sprites

I have over 197 sprites in a scene. 11 are the same sprites as Sprite A, 33 are the same as Sprite B, another 33 sprites are the same as Sprite C(these sprites are actually the same sprites as Sprite B, but with different sorting layers and coordinates), and finally 120 sprites are the same as Sprite D. Now the most obvious thing that all of these sprites have in common is their material. They all share a Sprites/Diffuse material for lighting. What I want to know, is how can I reduce the number of draw calls that these sprites make?

So far the average amount of draw calls is 30, which works on Mac fine but horribly lags on my mobile device. So again what can I do to reduce it to at least 20? By the way, when I disable all the sprite renderers, the draw calls drop to 16, just a note. Also only the 11 that are the same as Sprite A are set to the default sorting layer. Everything else is on different sorting layers than the default.

http://forum.unity3d.com/threads/draw-calls-for-sprites.249207/ Maybe this can help.

Have you looked at sprite Factory in the asset store.

I know it coasts £25 but its well worth it.