Which running app do you find most accurate?

initially I started out using map my run on my iPhone- I got the Apple Watch and transitioned to using the health workout app. After a small snafu with my Apple Watch I had to use map my run again. I noticed map my run gives me better pace/distance them the watch app. IE tonight's run:

map my run: 2.95 miles, 10:40/mile

watch: 2.87miles, 10:58/mile

Not wildly different- but I want to stick with whatever is most accurate (even is it mean getting a different app). 

Hello P! I do not have an apple watch, I have used map my run and an app by Nike. most folks I know use mapmyrun. I have not read any reviews on either to verify the accuracy. I have found that when mapping distances with my car I get a different number than mapmyrun.

I started with the Couch to 5k app.  It seemed decently accurate.  Once I finished that program I used Runkeeper.  It was also decent, UNTIL I got to over 6 miles.  After that it became pretty inaccurate (like saying I ran 6 miles but it was actually 4.5).  Had to buy and actual GPS running watch once I got more serious about it. 

Edit to add it seems that most phone apps have this problem of being inaccurate at longer distances, so changing apps may not help as much.

I haven't found one that I can say for sure is accurate. I can use Nike + GPS and runkeeper and map my run all at the same time (poor battery on my phone) and get very different results.