I would like my world to be always night time, but there appears to be no option to change this. So is it possible to make it always night on my world?
As of 0.16.0, you can change the time to night one time by
/time set night
To make it night constantly, (or if you are on lower versions then 0.16) you can use a mod:
Simple Commands mod adds a few new, simple text commands. Now, among the "standard" commands will have a new command that has the effect to your character. In total there are 23 different effects, such as speed and invisibility - it is the effects of potions. With these commands, you can affect the gamegame mode, weather, time, deceleration time, set the level of experience, and more in MCPE 0.11-0.15.7
pocketInvEditor mod (available on Google Play)
PocketInvEditor is an inventory editor for Minecraft Pocket Edition. With this tool, you can give yourself more blocks and items without writing a single hexadecimal digit or connecting to a computer.
- the mod also allows locking the day/night cycle
Not possible without a mod. This is a good one: