Being digital and portable doesn't guarantee that a device will be useful. I usually show services and devices that I heartily recommend, but now here's a friendly warning about gadgets you should be cautious about - they might be just (digital) dog and pony shows! 1. Calorie count from photos. You take a photo of your food and the app tells you the nutrients it contains. It's not even accurate when you weigh portions of your food and add those to an app like MyFitnessPal, so imagine how accurate those could be, using only photos. 2. Cheap tools to measure heart rate and sleep quality. If you want to take your tracking endeavors up a notch, you can't succeed with a single app or device just above the very basic level. 3. Pulse oximetry apps. You can install them for free on your phone, but unfortunately they are inaccurate - even studies show. 4. Genetic ancestry tests. It's thrilling to take one. But don't try to gain any medical insights from it. And definitely don't try to prove anything with it at your visa application. 5. Multifunction devices that can measure your vital signs, earthquakes, and the mood of your family. Maybe even killing mosquitoes. If something sounds too good to be true, it is. Which #DigitalHealth service didn't live up to its promises for you? …see more