Question from a developer:
How can we set up a matchmaking process which makes sure that player who aren't active any more aren't included (since non-response on challenges tends to result in abandonment)? Also, what about randomly matching players in the same region or who have the same language?
In general, your best method would be using the method described in this post (https://community.playfab.com/hc/en-us/community/posts/207129407-Persistent-turn-based-games-), as it provides for real-time matchmaking among active players, and lets you apply multiple filters via the parameters (skill and/or language setting).
Another way to do this though, would be by using resetting statistics/leaderboards (https://playfab.com/new-feature-resettable-leaderboards/). If the leaderboards reset each week, then if you grab the people around you in score, you'll only get people who played recently. In this case, you'd need to have separate leaderboards per language, if that's a requirement for your title.
