Google Translate gives C'est ton tour. Is this what you would use, when telling a friend it's his turn in a game? To give an example, I'm playing a friend in Words with Friends (a lot like Scrabble) and I would like to say to him, "It's your turn".
Here is a couple of common ways to say it:
[C'est] à toi
C'est à ton tour [de jouer]
Dropping the à is possible too:
- C'est ton tour
Here is, as I discovered thanks to your very question, quite a localized one:
- Ça vient à toi (Marseille area only!)
To answer to your first comment, note that à mon/ton/son tour is an old "set expression".
Quoted from: Curiositez françoises pour supplément aux dictionnaires Antoine Oudin, 1640
How you tell your friend it is his turn to play depends how close you are and how formal you want to be. From very formal to complete slang:
C'est à vous, chère amie!
C'est ton tour!
À toi de jouer!
Quand tu veux, mon neveu!
Z-y-va, pose tes tuiles!
I was playing bridge online with a couple from Canada this morning, and they used "tu joues".