Sorry, but I was dissapointed after downloading this product. The buble level has no calibration button, so mine is always seven degrees off of level! The same lack of a calibration button for the plumb bob, and it is -1.6º off! Ironically the angle finder is 3º off and does not match the bubble level, showing a software glitch. The flashlight only turns the screen white. If your screen brightness settings are set dark to save battery power, it will not light things up very much. You have to go to the home screen, settings, change your brightness level, then go back to the iPocket Tools application, select the flashlight, and turn it on. When you are done using the flashlight, you would of course need to go back to the settings screen to change the brightness back down of course.