Doctor Who: Legacy has been released for Android, iPhone, iPad and iPod touch, giving fans something to get their teeth into before the Christmas Special and Matt Smith's final bow as the Doctor is aired.

The game seems similar to other match-three puzzle games, such as Puzzle Quest or the recently launched Marvel Puzzle Quest: Dark Reign in that there are role-playing elements as well, but there is much more depth in Legacy than most.

Multiple Doctors will be available to play as and you can build teams of companions past and present in order to give yourself more of a chance of defeating all of the classic Doctor Who enemies. The Cybermen, Daleks, Sontarans and others appear in different episodic chapters.

At the beginning, season seven is available to play, with new seasons being unlocked as you progress and even earlier seasons being added as free-to-play add-ons later. It is planned that all 50 years of Doctor Who lore will be covered at some point in the game as time progresses.

Doctor Who: Legacy is available free from iTunes and Google Play. There are in-app purchases for items, extra companions and other bonuses, but the game can be played without them.