tried it once and worked. Did not let it sit for 15 minutes and tried it again. Did not work. Product works.
Fun iphone attachment4/24/2013
Fun attachment for your iphone - and practical too.
The entire process is a little slow when doing calibration, but this was in the product description. Have used it one night so far, and I was honestly surprised with the results. Playing to the side of error, I assumed the reading to be accurate (although I have nothing to compare it too).