Playing on a Pixel 3a is a really bad experience. The framerate seems to struggle to get above 20fps. I know the phone is not the most powerful, but other games run fine. Ive tried re-installing, manually setting the framerate and vsync in the options file, but nothing works.
I have the same phone and I’m experiencing the exact same issue. And as lapengu said, all other games run absolutely fine and hearthstone seems to be the only one that’s laggy as hell. I really hope the devs can do something about this.