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not sure about the UK, but in the US there are a couple ways.

time warner cable has an app that will run on the iphone/ipad, you can airplay from that to the TV.
check to see if your television provider has an equivalent.

also slingbox, which you hook up to a cable box, then that will convert and stream the output to your phone, which can then be airplayed to your aTV.


both require a current cable subscription though.


in the UK, you can use the BBC iplayer app on your iphone/ipad/ipod touch and should be able to airplay that to the aTV,
I'm not sure what that has in the way of live TV.

or another alternative, look at the products form EyeTV
 
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