After reading this, I just glued (removable) a 90 degree led lens to my phone. Nice results so far.

Edit: Link to such a lens: http://www.alibaba.com/product-gs/611389199/Led_Light_Lens_9...

I am happy that I turned my phone into a macro camera for a few cents. :)

Edit2: sorry, I used a 60 degree lens, not a 90 degree one.