Which Digital Level Gauge to buy?

Stringreen/Taylor514....There is no way a carpenters level can get the same results as a digital gauge. Change the angle of view of the bubble just slightly and the level reading changes. The digitals are accurate to 0.1 of a degree. Impossible with a regular spirit level. And as a level table is as important as VTA or any other TT setting it is vitally important with a high end rig running contact line type stylus that this is as perfect as possible.

Hiendmuse....does the CartridgeMan unit fit over the spindle or do you just place it on the table somewhere else?

I can see how that would make a difference if the gauge is heavy and it affects the level on a sprung TT. The DigiPas does not fit over the spindle but does weigh less than the CartridgeMan unit.

There are over 20 Apps for levels in the App Store.
The problem with the App levels is that they all need calibrating. So who has a 100% level surface to do that on? They might get you closer than a regular carpenters bubble but from what I have read in the reviews they are not close to the accuracy of a dedicated tool.

I just downloaded a twin axis level app called Gyro Level.
It works from the internal gyroscope in the iPhone so does not need calibrating.
It aligns using gravity.
I would love to find a level table to check it on as this thing could be the $0.99 answer to the $350 question!

Dougdeacon.
I agree with your comments.
Certainly about the phone apps.
That's why I would love to find a level table to see how accurate this app/phone is.
And yes, you really can get a good result from a bubble level but I would suggest not nearly close to a good electronic devise.
Since purchasing my SME 20/12A and Soundsmith Strain Gauge cartridge I have become acutely aware of how the slightest changes in geometry and level radically affect the sound.
With this kind of money invested I feel that a couple of hundred bucks more to ensure a precise level is money well spent.
Technique is king...but a great tool used correctly is the ultimate solution in the end. And which of us doesn't love a great tool :-)