Player.me might be a bit more popular than Game Center. We know about 1 link to it since March 2021 and only 1 link to Game Center. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
u/JTostitos is right though that Game Center was designed for this although it has gone out of style with many game studios lately. But it all depends on how the game is designed... If you require constant client-server communications then implementing Game Center doesn't really make sense when you can easily roll your own leaderboard on the server. Source: almost 2 years ago
It's even "better" on their homepage. No mention of other services. Source: about 2 years ago
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