These features were once in Minecraft, but were removed.
List of Removed Features[]
Cyan Flower[]
Cyan Flowers were once in Minecraft Pocket Edition as replacements for the Rose. They were removed in Update 0.9.0 when they were replaced by Poppies.
Camera[]
Cameras were added as a way to take screenshots in-game. They were only accessible through inventory editing and were removed in Update 0.9.0.
It was stated it may be re-added with a proper image sharing system.
Gravel Paths[]
Gravel was used as paths in Villages, but in Update 0.11.0, they were replaced by Grass Paths.
Nether Reactor[]
The Nether Reactor was replaced by the Nether dimension in Update 0.12.1.
Nether Reactor Core[]
Nether Reactor Cores are just what the name implies: the core for the Nether Reactor. They were removed along with the exclusion of the Nether Reactor.
Glowing Obsidian[]
Glowing Obsidian is what the Nether Reactor Core reifly turns into when activated. Since it was a Nether Reactor related block, it was removed due to the Nether Reactor being removed.
Stonecutter[]
The Stonecutter was removed from Survival Mode in Update 0.13.0, and its functions were moved to the Crafting Table. It can still be found in the Creative Mode inventory.