How do you complete level 12 on floors?

Answer 1

On level 12, you need to press the red buttons until they reach the top of the column and light the tops. After you get both balls there, the doors will open. Try pressing the buttons with your thumbs while tipping your device different ways if you get stuck. Sometimes it doesn't work well in one position.

As fast as you can tap both the red buttons until the top of the 2 pillars are green
Press both of the red buttons fast until both green lights light up. See related link for screenshots.