Nether Reactor

The Nether Reactor Core is a block, exclusive to the Pocket Edition. It is used to create the Nether Reactor.

Crafting
Crafting it requires three diamonds and six iron ingots.

Nether Reactor
The Nether Reactor is built with a nether reactor core, gold blocks, and cobblestone, arranged in the following configuration:

Note the block in the center of the middle layer represents the Nether Reactor Core.

Top layer:

Middle layer:

Bottom layer:

When the Nether Reactor is built and the core activated, it generates a room of obsidian with some openings, around the reactor. The reactor itself will turn into a new block resembling netherrack, and it will start spawning various items and blocks, such as gold, as well as Zombie Pigmen.