variance of +/- 10 Hz with 1 kHz test tone

My phone locks onto a 1kHz tone with the app. I have the latest IOS, unfortunately. Go to info and see if you have the latest version of the app. Under "Prerequisites" It should say that it now works with a 1000Hz tone. It is not as accurate vs. using the 3150Hz tone.

Wow&Flutter is the magnitude of speed variation during platter rotation. That means the frequency will vary proportionately if playing a constant frequency tone such as 1kHz or 3150Hz. It is the product of motor speed variation, eccentricities of the record, platter and motor pulley plus roundness of the platter and motor pulley, if using a belt drive turntable. It is typically considered to be a periodic variation. The iPhone app is based upon that assumption and generates a filtered value to eliminate the influence of test record's eccentricity on the final value. So if the platter is mounted eccentric to it's bearing center, this app will mask that issue as well. Simply watching your platter and/or record for side to side motion during rotation can confirm how well they are centered. If you want to really feed your nervosa, borrow a dial indicator from a machine shop and measure the out of roundness and eccentricity of your platter. I'm not going to do it. No I'm not. No sir. Please don't make me...

Play some music with piano on it. Not necessarily rock&roll.

Look for something that is moderate or slower in tempo.

You should be able to hear whether a variation of the degree you desctibe is noticable or objectionable.

Report back to us & tell us: "Wow, does this have flutter"

Hopefully it is a non issue.

That level will make a difference in clarity, decay, imaging, even if you notice no obvious speed instability.

I've seen a lot worse on a lot more expensive turntables, brand new. That does not make it right.....or good......but it's not unusual.

Should I try another platter to see if my current factory Rega one is defective?

If I'm not mistaken that level of performance translates to .02% away from what a casual internet search showed to the best to be, a VPI TT with .01%

Anything that bests .1% exceeds NAB specifieations.

"Wow and Flutter Factor (Re~ording)~
1.15 It shall be standard that the average deviation (measured over the range 0.5-200 cps)
from the mean speed of the recording turntable, when making the recording, shall not exceed
0.04% of the mean speed. The average deviation above shall be measured by a meter the dynamics
of which shall be the same as those of the VU meter as specified in ASA Standard C16.5-
1961.
Wow and Flutter Factor (Repr~ducing)~
1.20 It shall be standard that the average deviation from the mean speed of the reproducing
turntable when reproducing shall not exceed 0.1% of the mean speed."

I can't remember anything that would suggest the NAB would want to drive listeners away from either Am, FM radio because they were sloppy or uncaring with audio performance.

Because today, many turntables routinely perform in the range of .03% or less can't possibly mean your head might spin when listening or that performace in the .03% to .01% isn't top notch.