I just did this as a reply to another topic. An easy way to backup and run applications from your SD CARD is to go to the Android Market and download App Manager. It is free and what it does is backup all the applications that you have on your phone to your SD Card and also it allows the option to run all the applications directly from the SD Card. I just did it and it worked. Try it out and comment on how it works.
In response to the replies, yes I was a bit wrong. However this does help in certain occasions such as if one downloads an application and wants to back it up and/or share it with another person. In my case, I wanted to find a way to be able to share MP4 Youtube downloader with my friends as it had been removed from the market. But I am thankful for all the criticism as it is better to right than partiallly right. Sorry for misleading anyone.
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