Turntable leveling

I have a pretty decent setup which satisfies my commercial grade bubble level. One day I was adjusting something -the thing is HEAVY- and the front right cone fell over. I set the table back on the fallen cone which caused the table to tilt to one side by about 1/4 inch. I played a few LPs and didn't notice anything particularly out of kilter. Which is nuts... because I can detect 0.25mm VTA! It's all relative.

Thanks, everybody! My blind trust in a free "high tech" phone app may be misplaced. I'll trust the bubble level even though it's a cheap one. Maybe I can borrow a better quality one just to check.
Keith

noromance

... because I can detect 0.25mm VTA

Not likely, especially because common LPs aren't flat within .25mm. If you're convinced you can hear a deviation that slight, it suggests that your stylus may be chipped or damaged. That could account for your claim.

I use an "analog" bubble level, and that seems fine.  So my answer to your question is don't fret over it.  On the difference between your phone app and the ordinary bubble level, I'll go with the latter.  I have an "audiophile" bubble level, meaning you center an air bubble in a circle, unlike with a carpenter's level, where you need to level it in two directions. If the bubble is just barely touching the inside of the inscribed centering circle, that's acceptable to me.  If the bubble edge lies outside that circle, I adjust to correct.