Media reports suggested that Cameron had re-signed with the Browns, but the Dolphins confirmed the arrival of the 26-year-old on a two-year deal worth $15m.
He arrives as a possible replacement for Charles Clay, who is still being pursued by the Buffalo Bills after the Dolphins gave him a transition tag.
Injuries disrupted Cameron???s last season and he managed only 24 catches, gaining 424 yards, with two touchdowns.
But he still proved his worth, leading all NFL tight ends with four receptions of longer than 40 yards, including touchdowns of 81 and 51 yards. ??
He made the Pro Bowl in 2013, when he had 80 catches for 917 yards and seven touchdowns.