Is there a limit to the amounts of friends a player can have? Even if there's not one, do you suggest any magic number that we should stick too (performance-wise)?
There is no specified limit to the amount number of friends. If a player had a very large number of friends, he will eventually get time out error when waiting for response after GetFriendsList API is called. In addition, the response time also depends on the network connection quality. I believe you need to test it on your own. Theoretically, PlayFab should be able to handle at least 5000 friends. But as I have noticed in some popular modern games, developers tends to limit friends list to few hundreds. Even MMO like World of Warcraft only provides 200 friends slot, which has been expended once and it was 100 in the very beginning, while in most mobile games, the number is less than 100.
5 People are following this question.