The new 0.9+ world generation allows infinite worlds, and has a different world system than the other versions, so sadly it doesn't use the chunks or entities.dat anymore.

Do you want to play some maps like Skyblock in Minecraft PE? This guide made by the OrangeSox will show you how to do it without a jailbreak. It is for iDevices, not Android. I believe it is similar on Android though. Here's what you'll need:

A computer
Your iDevice
A cord that connects the two
iExplorer (click here) or iFunbox (click here) (You only need one, and I prefer iExplorer)
A map you'd like to play



Step One:
Go on your iDevice. Go to your multitasking bar (double click home button). Find Minecraft PE. Hold down on it. A delete symbol will appear. Click it. This will not delete Minecraft PE, just shut it down, so don't worry.

Step Two:
Now, you can turn off your device. Plug it into your computer.

Step Three:
On your computer, boot up either iExplorer or iFunbox.

Step Four:
Go on to the web (on your computer), and find the map you'd like to play. I suggest looking on MCPE Universe, it has a good selection of maps. Download the map you want. Drag it somewhere (I recommend your Desktop).

Step Five:
In iExplorer/iFunbox, you should click Applications and you should click these (I'm not sure if I wrote these right, but it'll look something like this):
Applications
Minecraft PE
documents
games
com.mojang
minecraftPEWorlds
Okay stop!

Step Six:
In the minecraftPEWorlds folder, you should see a list of folders, each labeled the names of your worlds. Inside them are a few files: chunks.dat, entities.dat, and level.dat. You may also find: level.dat_old, and player.dat.

Step Seven:
Drag the world you downloaded into the minecraftPEWorlds folder. Make sure you don't put it in one of your worlds, because that will mess it up.

You're Done!
You can remove your iDevice and play the map you just installed!