Frustrated with 2 apps, Walk My Dog and MapMyFitness

2bassets

I walk every weekend and usually use Walk My Dog App, as they donate to the Rescue that I support. Yesterday, I thought I'd try MapMyFitness and see if WMD was comparable. MMF was a shorter distance than WMD for 2 miles. Granted, it was about 100 steps shorter, but when I'm walking 4 miles in the morning and 6 in the evening I'd like to know which is correct. Someone had mentioned that I needed a Garmin for accuracy, but wouldn't you think that these would be somewhat accurate?