The Fitbit Flex is an activity tracker aimed at measuring your exercise, diet and sleep. The device was my constant companion for about a week, and by the end of it, I felt informed about my activity levels, and was motivated to get moving.
Whether we like it or not, we're constantly judging the intelligence of others, estimating their level of competence by evaluating their responses to our questions. Some people are better at detecting intelligence than others, but that doesn't mean you can't learn how. With practice, you should be able to gauge the intelligence of others with a decent degree of accuracy, though you should always be prepared for surprises.
IQ tests were meant to find out what the most suitable way to teach someone might be. Someone with an IQ of 75 probably needs extra help, while someone with an IQ of 125 probably needs more challenging work. SO, IQ doesn't tell you how smart you are, just how you compare to other people at different ages. Intelligence is a quality, not a quantity.