Probably improved since 2019 but I highly doubt to a level in...

Probably improved since 2019 but I highly doubt to a level in which anyone can grab their phone and get an accurate measure. These advances take a loooong time due to the almost unlimited amount of outside influences that the tech needs to be able to account for such as the ones stated earlier; skin types, lighting, temperatures.
I'd expect it to be useful tool to estimate but not accurately measure for many years before they can get it to that level.