How do I remove the debug console window on my iPhone?
Apple includes a Safari debug console for developers in the iPhone firmware. Some users have turned this on without realizing that it's unnecessary to them. In fact, it takes up already limited screen real estate when running Safari and is generally annoying if you have no interest in the console.
To turn off the debug console window:
Settings -> Safari -> Developer -> Debug Console -> OFF
To turn the debug console ON repeat the steps above. The debug console was included by Apple to help developers resolve webpage errors. When the console is turned ON it appears automatically when a webpage error occurs.