What's the ID of monster spawners in Minecraft Pocket Edition?

This command will place a mob spawner that spawns an entity of your choice.

/setblock x y z mob_spawner replace {EntityId:id}

• x, y, and z are the coordinates where you want to place the spawner.
• id is an entity ID. You can find a list of them in the Minecraft Wiki article.

Examples:

/setblock ~ ~ ~ mob_spawner replace {EntityId:58}      
     places an Enderman spawner at your location

/setblock 4 20 -289 mob_spawner replace {EntityId:Zombie}
     places a Zombie spawner at the coordinates (4, 20, -289)