If you've been around this site for a while, you'll know I'm a runner. I've had a bit of an obsession with running apps for a while. I regularly try out new ones and while there are a few I use semi-frequently, the one that's stuck through the years is Runkeeper.
I started using Runkeeper back in 2009 (I think), and have used it on every run since 2011. I even signed up for the Elite membership because I like the advanced reports. Also because I want Runkeeper to stick around.
The guys at The Sweet Setup picked Runkeeper as their favourite run tracking app. It's a very thorough article and worth a read.