Me and my Wife both recently got Galaxy watches and there is a major bug with the app in that the average running speed shown is all over the place and not steady at all. Once the data is uploaded to Samsung health and finally (see other post) to Strava then the average speed sames to be recorded accurately.
Most runners run to a targetted average speed so not having this shown consistently is an absolute pain in the neck. Please try and fix this asap otherwise I'll be going back to my 5 year old Garmin which shows average speed consistently and is far better for running.
Also is there anyway to set the display to permanently show the running stats whilst running is going on so I don't need to lift my arm right up to get the display on.
I have the same issue bicycling. It used to work perfectly, giving average speed for the entire trip. Now it seems to be giving the average speed from the last mile, so it varies quite a bit. Once the trip is complete, the average speed is accurate. I think the problem started with the last update.
I have the strava app installed. It's pretty good but the pace display is *horribly* wrong. It seems to get straightened out after upload to strava, but while running, you may as well not bother. Often it's 10'/mile too slow. They have a SW problem. Hard to say if it's Strava or Samsung at fault, really.