Hi! Thank you for a bug report.
Which graphic settings are "bad"?
If you're talking about a decrease in free memory, it's possible it's not a memory leak, but simply the loading of assets as the game progresses.
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I think the problem is not in the graphics, but in the inefficient use of RAM by the game. That eats too much of it and it gets to the point that the phone starts to glitch badly because the RAM is at its limit. I don't know if there is a built-in memory cleaner in the game or not, but it definitely needs to be worked on. And so the graphics should not eat much either.