Sounds like pretty much the same thing, although the calorie estimates seem more reasonable (to this uneducated shmoob, anyway).
RunKeeper also has an optional heart meter accessory you can hook up to it.
One really nice thing about RunKeeper is that it integrates with all the sites I use -- I can post my walks/bikes/whatevers to Facebook straight from the app, and Fitocracy can pull in my RunKeeper workouts to earn me points there. I'm sure Endomondo can post to Facebook too, but I don't recall seeing it as something Fitocracy can pull from...
RunKeeper also has an optional heart meter accessory you can hook up to it.
One really nice thing about RunKeeper is that it integrates with all the sites I use -- I can post my walks/bikes/whatevers to Facebook straight from the app, and Fitocracy can pull in my RunKeeper workouts to earn me points there. I'm sure Endomondo can post to Facebook too, but I don't recall seeing it as something Fitocracy can pull from...