Now that MPO is online and working for people, here is a guide for those who may not know how to connect to a server just yet. Mojang has not yet implemented a server connection feature in Minecraft Pocket Edition, so we have to connect in a different way. What we will basically be doing is fooling MCPE to think it’s connecting to another local MCPE server hosted on a phone or tablet.
First off, you’ll need to download and install the free app PocketTool (available on the Play Store). You’ll need to know the server IP address to play.
Secondly, open up PocketTool. Press the button for the tool kit.
Now that we’re in the tool kit section, select Change Server IP.
Now type in the IP address. The “http://” isn’t necessary here.
Now hit “Patch my IP!” PocketTool will patch your MCPE installation. After it says it is done, press the menu button on your phone/tablet. Choose apply changes. This is the point that can be unnerving: it is now going to ask you to uninstall Minecraft Pocket Edition. Click OK and let it uninstall MCPE. After it is finished, it will ask for permission to install MCPE. Click OK. PocketTool is simply removing the original, unpatched Minecraft and replacing it with the patched version. When this finishes, you should be able to choose and play on the server you’ve just added.
Just join and enjoy now, you’re done!