MFP with iPhone/Apple Watch

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I use MFP to measure my calories and when I run I use the Apple Watch which, with the phone syncs my calories to MFP. Might be a dumb question by should I count steps as well? I work at a hospital and on my feet a lot over a 12 hr period. I decided to turn on steps for fun and it gives me a goal of 10k. I am already over 8K with just over 4 miles and 377 calories burned. My question is how accurate is it and should I bother even considering these "burned calories"?