Screen goes black when I play Infinity Blade

Question

I was playing Infinity Blade on my iPhone 4 and I selected game center option to look at my achievements and when I push the "Done" button, the screen went black. I exited the app and went back it is still black.

How do I fix this issue and return to the game?

Answer

The reason the app is still black is likely because it is still running. Try exiting to your Springboard (home screen) and double-tapping the home button, bringing up the multitasking bar. Find Infinity Blade, and hold down your finger on the icon. They will start to wobble, like you are rearranging apps. Press the little minus icon on the Infinity Blade icon - this quits the app. Tap anywhere on your home screen to return, and try launching Infinity Blade again.

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Why is my piston powered cobblestone generator crashing minecraft?

Question

I was trying to build an automatic cobblestone generator using pistons, and while I think the machine should work, it instead causes the Universe to implode game to crash.

The stone is created from water and lava mixing next to a "top" piston, this then uses a repeater to transfer power through the stone when it created and activate the piston - pushing it directly downwards. A few levels down is the "output" piston, which uses the same trick detect when a block has been pushed down in front of it, and will then push it sidewards out of the machine.

The top piston has an override "off" switch in it's loop, which works as a start/stop override for the whole machine.

When I switch the machine on Minecraft crashes - I can just hear a piston going and then "Saving Chunks" and darkness...

Luckily, it seemingly crashes in a recoverable way, my world is still playable after a restart, but with a few "phantom" blocks clogging up the machinery...

So, what's going on and how do I fix it?

Oh, and I'm running version 1.9pre3 with no modifications.

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Images of the machine:

Top Piston Construction:

Bottom Piston Construction:

"Phantom" Blocks:

Answer

This is a bug in the 1.9 pre-release (not sure if just pre-release 3, or all of them).

As you can see here:

It's working as you intended it to in 1.8.1

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