MangoHud
5.8#20 in game overlay softwareFree planFree planLinux
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MangoHud suits Linux users who want an overlay for graphics performance and hardware metrics. It can also help users who want to log frame data for later comparison.
OP.GG suits players who want game statistics, player profiles, rankings, or game-specific information. The listed services cover several competitive titles, with some offerings still marked beta or coming soon.