True, but the binax test for instance has clear photographed examples of what positive, F pos and erroneous tests are. I do not trust a bluetooth reader over a human interpretation - if it's ambiguous to read, we should know that, right?
Why are examples useful? Is there an example of "This is the minimum that counts as positive"? What if I am unable to visually distinguish that example from a negative? If I am able to visually distinguish them, then what if there is a line but it's fainter than that minimum? You can't guarantee that both of these are impossible, because different people have different visual capabilities.
https://www.fda.gov/media/144574/download page 6. It shows different gradations. That's what i'm saying, if you cannot tell the differnce in the instructions, you know not to trust the result
If the reader is calibrated and tested to be as good as a trained human with perfect eyesight, that seems better on average than relying on untrained humans with unknown eyesight. Heck, it could even be better as it would be able to supply a controlled lighting condition by measuring off a known LED.
