Same issues here. I got an Ultra back in mid March. I spent two weeks running totally frustrated with the HR missing more than half of my run. As soon heart beats go above 135 BPM (it seems to be my magic number) the watch gets lost and just recovers readings almost always 10+ minutes later (but still on and off). After looking around and trying tighter, looser, upper arm, inside of wrist, bla bla bla…same problems. For sanity check, I went for a run with the Ultra on my left arm and my wife’s 8 Series on my right arm. For my surprise the Ultra lost more than half as usual, 8 Series didn’t miss a beat.
I went back to Apple Store and replaced my Ultra thinking I had a defective unit. However, new unit and same old problems.
Anyway, I’m more inclined to believe it’s poor hardware/software interface. It’d be weird Apple having a different software running on 8 Series and Ultra. They might share the same software, but the weight/size/shape of the Ultra may requires a different solution (maybe even hardware…not sure if it’s the same as 8 Series).
Below Heart Readings from my last 20 minutes run and a fast pace walk at the end. Difference is abismal. Running it got just a bit more than 4 minutes readings.
I loved the Ultra: concept, design, features; and I was so looking forward to go diving with it. But there’s no point of having an outdoor smartwatch that can’t monitor heart beats.
Now it’s time to return the Ultra again and decide if I move to a 8 Series or other brands, because it’s pretty clear Apple is not concerned at all on fixing this problem. Apple isn’t the same anymore and I’m on the ecosystem since 2009!
