I jailbroke my ipad3 and purchased Display Out app.
How do I use it? ( I am low tech and still trying to find my way around).
Also, did I waste my money as I could have just bought an adapter cable linking my ipad to my HDTV and used an HDMI connection.
Grateful for any comments and assistance with how to use this device properly.

Display out app tweak helps other apps be compatible with "display out" type method if it didn't have that option. Not sure if there's a SBSetting toggle switch for that.

It's hard to say whether you wasted your money or not
You need to tell us why you wanted the tweak in the first place. What app is it that you want to display externally, on what device, and what cable do you own at present to do it?

I use DisplayOut a lot to show apps which do not support VGA out to be shown on projectors at work via the iPad VGA adapter cable. For me it's been totally worth the investment.

But if you just want to show your iPad3 screen on your HDTV, the official HDMI cable may have been suitable for your needs without any additional tweak or app. It's hard to say without knowing exactly what you want to show on the screen...

I really think that I did waste the money and i will be reverting back to a normal configured ipad.
Might try jailbreaking again once I know what I am doing!