Stravistix is a free analytics and monitoring utility that is somewhat comparable to TrainingPeaks, SportTracks and the like. It’s a Google Chrome Plugin that adds more data and information to your Strava data. It is recommended to have Strava Premium to get the most out of it. While it’s not as robust as the previously mentioned tools, it’s a great addition to your Strava data.
Works with Google Chrome and Opera
Stravistix for Google Chrome
Stravistix for Opera