This is a great and stable app with many features for those who wish to log their travel and exercise.
The project is struggling for funding. So please support the developer if you can.
The great thing is that they have developed a feature to import data from the similar Moves app which has now closed down. I tested the Arc app against Gyroscope, Loca and Instant. Arc won hands down on usability and accuracy. And they keep launching new cool features. Two thumbs up!