Follow along with the video below to see how to install our site as a web app on your home screen.
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If you are rooted then there are a lot of apps that will do what you are asking. If you are not rooted then there is an app called No Root Screenshot It that will work. I have it setup where it will take a screenshot if I long press the search button. The first time you use it you need to download some software on either a PC or Mac and plug in your phone to enable it. Pretty straightforward instructions.
No Root Screenshot It
Nope, just the first time. It must just make some change to your phone.
If you reboot your phone you have to enable again on your PC via-usb. It only takes seconds though. I have it also.

We get the screen shot with the upcoming ICS update, too.