Mr Conlon's family issued a statement through his lawyer Gareth Peirce.
This morning we lost our Gerry.
He brought life, love, intelligence, wit and strength to our family through its darkest hours.
He helped us to survive what we were not meant to survive.
We recognise that what he achieved by fighting for justice for us had a far, far greater importance - it forced the world's closed eyes to be opened to injustice; it forced unimaginable wickedness to be acknowledged; we believe it changed the course of history.
We thank him for his life and we thank all his many friends for their love.
More top news
MPs say there is a "severe conflict of interest" in F1's sale to Liberty Media after it emerged the governing body benefited from the deal.
Freezing with frost and fog
A ticket holder in Ireland has won tonight's EuroMillions jackpot which was an estimated 88.5 million euro (£76 million), Camelot said.