It has a very limited use AFAIK. There's only a couple of uses that I know of.
You can use it on Hearts or Rupees to change them. Hearts turn into Fairies. Rupees turn into different valued rupees, even a Rupoor.
On some of the smaller enemies, it knocks them dizzy. I was only able to do this on Bokoblins, Octorocks and Babas (the plants) but didn't have enough to test on others.