In DragonVale for the iPhone and iPad, the Current Dragon is a hybrid dragon with the water and lightning attributes, similar to the Plasma Dragon.
To get a Current Dragon, you need to breed a Water Dragon with a Lightning hybrid. Some examples are Water + Storm, Water + Magnetic, etc.
Note that any of these combinations do not guarantee results, and the different combinations have different percentages for success. Keep trying though and you’ll eventually get your Current Dragon.
Check out my DragonVale Breeding Guide for more dragon breeding combinations as well as other Lightning hybrid combinations you can use to get your Current Dragon