How do I choose a "Medium" difficulty?

Solution 1:

The settings currently are:

1. Peaceful: no mobs spawn and attack you
2. Regular: mobs spawn and will attack you; similar to the normal difficulty on PC.

Solution 2:

The only options are difficult and peaceful. Unfortunately there is no middle. If you are looking for less mobs, all I can suggest is keeping your world well lit by placing torches or glow stone.

Solution 3:

The slider is basically a fancier looking version of the Peaceful Mode option in previous versions of Minecraft: Pocket Edition. Sliding it to the left enables Peaceful Mode, and sliding it to the right is regular survival.

Solution 4:

After upgrading to 0.12.1 you will have four options for difficulty. the max appears to be same as normal mode of old and the lowest is peaceful mode of old... the two in the middle seem to be the medium you are looking for.

there is still no hardcore option for PE

frankly the max position hasn't been much of a problem so I'm not even sure it is the worst possible but it is logical that all the way to the right will be the worst available.... Try it, you might like it!