Introduced in version 0.6.0, Signs are blocks that allow the user to type on if desired. They can be placed on walls or on the ground with many different angles.
To craft a sign you need 6 wooden planks and 1 stick. When placed on the edge of stair blocks it can be made to look like a chair. Once placed they can only be edited by removing and placing the sign again. Unlike the PC version of Minecraft, crafting a sign in Pocket Edition yields 1 sign, whereas in PC you get 3 signs from the crafting recipe.