4 stars: the app is pretty good and seems to be a good metrics. but I wish it would also store the heart rate when I record, as I need to keep track of my heart rhythm whem standing up or sitting down. the flash also gets pretty hot, and it only factors in that healthy people take the app. I have pots, so my standing heart rate is naturally higher, making it think I'm running or stressed. I'm not I'm just standing.
2 stars: After a couple of months of successful measurements suddenly every one was
2 stars: I find the HRV measurement interesting and maybe useful. I would have continued using it, and might have paid for it, but the interface is incredibly cluttered, and I get pestered with unwanted notifications.
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