I think many already know that in Minecraft PE added console command, which is detailed enough where it is written. In this guide I will try more to describe the essence of each commands.
So, the full list and a note for each commands:
/? or /help - help command reference. Print the full list of commands in multiple pages.
/clone - copies a region from the first two coordinates in the third.
/gamemode <0/1> - set player survival mode(0) or creative mode(1).
/give - give items.
/kill - kill player. (you can't kill the player in creative mode)
/list - show list of players connected to the server.
/op - gives the specified player operator.
/deop - to take the player to the operator.
/say - write something in the chat.
/setblock - set the block at the specified coordinates.
/setworldspawn - set the spawn for all players.
/spawnpoint - set the spawn for the player.
/summon - spawn a creature by the coordinates (for example, /summon lavaslime 5 5 5).
/tell (or /w, /msg - send a message to the player.
/time add - add time (to rewind).
/time set - set time. (for example, /time set day or night)
/toggledownfall - to turn on/off the rain.
/tp or /teleport - teleport to coordinates.
/tp or /teleport - teleport a specific player to the coordinates.
I am a professional from Minecraft PE Team that creates and publishes the best content for Minecraft players. We have been studying custom gameplay, modding features, as well as popular game themes for a long time. You can be sure that our materials are designed for the player to spend more time in the game world than usual. Additionally, our modifications will allow you to turn your game into absolutely any other theme. I'm also a pretty good player, so I'll try to answer any of the questions in the comments.