I was trying to turn off assistive touch where each cell is highlighted and continually goes on through the whole page. I saw a black box with a white button and on/off. I turned it on. Now, I cannot do a thing. I have this small black box with a

Welcome to the Apple Support Communities!

I understand you have enabled AssistiveTouch on your iPad. To turn the feature off, press the Home Button three times or tell Siri to "turn off AssistiveTouch"
Use AssistiveTouch on your iPhone, iPad, or iPod touch

There are a few ways to turn on AssistiveTouch. Do the opposite to turn the feature off:

• Go to Settings > General > Accessibility > AssistiveTouch, then turn on AssistiveTouch.
• Tell Siri “Turn on AssistiveTouch.”
• Go to Settings > General > Accessibility > Accessibility Shortcut and turn on AssistiveTouch.

When Accessibility Shortcut is on, you can turn AssistiveTouch on or off from any screen using Triple-click Home. Just press the Home button three times. To adjust the Triple-click speed, go to Settings > General > Accessibility > Home-click Speed.

To turn off your device, follow these steps:

1. Open the AssistiveTouch menu and tap Device.
2. Touch and hold Lock Screen until "slide to power off” appears.

You can also use AssistiveTouch to access your Home screen. Just open the AssistiveTouch menu and tap Home. To use Siri, open the AssistiveTouch menu and tap Siri. You’ll only see Siri on devices with iOS 5 or later.

Take care.