Through his career, Turner has made seventy-one Football League appearances as well as four Premier League appearances for Everton.
He also represented Scotland at under-21 level.
Turner has played for a number of clubs in his career including Chester City, Sheffield Wednesday, Preston North End, Coventry City and Sheffield United.
He spent last season with National League side Tranmere Rovers having joined in 2015.
Manager Alan Lewer told the club`s website: “We’re very happy to bring Iain on board and we think we have two very good goalkeepers now in the squad. We know he’s a great ‘keeper, Mark Wright and I knew Iain from Chester and we’ve been talking to him for about six weeks. Iain had been talking to a couple of National League clubs and waiting for things to materialise, but we kept in contact, we told him how much we wanted him here and we’re delighted to sign him.
“Iain will be competing with Mark Halstead for the number one spot. It’s a great scenario to have them both challenging and fighting for the number 1 shirt and we think it’ll bring out the best in both of them”.