I've been using Runkeeper for a while now. I'm not terribly active but it's kind of neat keeping track of my rare spurts of exercise. I've always been pretty happy with the android app and never really thought I'd need or want to switch to a competitor.
However, recently, I've been using a custom version of Android on my phone (Cyanogenmod 9) and runkeeper has stopped working properly. Typically, as I submit my "workout" the app crashes and the workout isn't submitted. Or, even worse, the workout is recorded as 0 minuts and 0 miles travelled. Sometimes, if I relaunch the app, and go back to that workout it fixes itself and the workout is submitted but not always. It's really getting annoying. I suspect the problem is in my custom Android and not runkeeper but it's still causing me some minor grief.
Thus, yesterday I decided to give endomondo a try. In both cases I'm using the free version. I actually installed endomondo a few weeks ago but after starting it up once I didn't bother trying to use it. I think there might have been a welcome screen or something that didn't seem immediately intuititive so I just forgot about it. However, when I launched the app yesterday the screen was very easy to understand with the exception of a small circle with the number 10 in it that made sense as soon as I clicked on it - it starts a countdown before the app starts monitoring my workout. That is a cool feature and runkeeper should copy it. The rush to get started as soon as I hit go always bothered me in runkeeper.
The problem I have with endomondo, and I again I bet this is related to my custom version of Android, is that it too crashes all the time. Endomondo crashes whenever I go to the main workout screen. Thus, if I change activity type it crashes. If I minimize the app and then go back to it it crashes. If I switch to answer a phone call and then end the call and return to the app it crashes. If someone calls me and I answer it, you guessed it, it crashes. It's very annoying. Thus, I keep getting these little abbreviated workouts recorded. It's not a big deal but it is frustrating.
At the moment I think I'm going to stick with endomondo - I like the fact that it at least saves my workouts even if they are all broken up into smaller segments due to the crashes; at least I'm not losing data (so long as I remember to restart the app after a crash). I also really like the delayed start button, honestly, if both apps worked I'd probably switch to endomondo just for that feature.
I also like the look of the endomodno app a little better and I really prefer it's post workout report screen over the runkeeper equivalent. Finally, I also prefer the workout history reports in the free endomondo website over the runkeeper equivalents.
So far my endomondo facebook integration which would share my workouts on facebook hasn't worked - but I don't really care. I'm not sure if anyone wants to see that stuff anyway.
If you are using endomondo or runkeeper I suggest you give the other a try and see which you like. They both track the same basic stuff but in a significantly different way that you might find you prefer the competitors approach over your current choice.