Today I found Texas Instruments announced a circuit for wireless charging - Ti BQ51013 Qi receiver controller - all the materials emphasis how tiny, lightweight, portable, efficient and otherwise cool it is.
While I of course like the idea I don't get one thing. What's so hard in implementing such circuit in just all cell phones allready? Every other company introduces so-called "charging mats" that also require en extra gadget attached to the wireless device to make it receive power from the "charging mat" and I guess different systems are incompatible with each other, but there're almost no devices with built-in wireless charging (except maybe shavers and toothbrushes).
It's year 2011 and we have microchips with millions of transistors on them - why don't we have such simple thing as wireless charging in every applicable device yet? What's the technical difficulty here?