The plans, which were first reported by Media Week in July, include both live TV and downloadable clips, including highlights and behind-the-scenes footage.
Under the 12-month deal 3's 3.2 million customers will be able to watch I'm A Celebrity's bush tucker trials before they air on terrestrial television.
The agreement will also extend to Emmerdale, Coronation Street and other high-profile shows and one-off specials in 2006.
ITV chief executive Charles Allen, said: "With big entertainment shows like these people increasingly want to get the latest gossip and content between shows.
"So we are delivering more of our quality content to viewers on their mobiles and online, supporting our programmes, and allowing viewers to access the latest content wherever and however they want it."
The agreement with 3 is the first of its type for ITV.