I used the IGCDroid for six currency flights yesterday in snow-less Iowa, and it worked perfectly. As the instructions say, turn it on while pre-flighting, then forget it. At the end of the day the IGCDroid presented six separate flight traces, with a maximum altitude gain of 16 feet (a feature of midwest winter weather, not the app) IGCDroid could not have been easier to use. Thanks for the hard programming work.