CoreSync: track heart rate, sleep and blood oxygen around the clock — premium quality at a fair price

At first I wasn't sure it would be useful — I bought it almost by accident because my wife had been pushing for ages. Three months in and I know when I've really slept badly, not just felt it. I also use it for heart rate on morning runs before work, and the battery lasts all week without charging every two days like my old one. I dock a star because the app sometimes takes a while to sync, but for the price it more than delivers.

I gave it to my mum for her birthday and worried she'd struggle to get used to it. It's not a "senior watch" — and I'm much more at ease: from the app I see if she's been walking, how her heart rate is, even alerts if something looks off. At first she only wore it to "try it" and now she never takes it off, even to sleep. Big buttons, crystal-clear screen. For anyone who wants to keep an eye on parents without overwhelming them — exactly what I needed.

I didn't expect this much info at this price — pleasantly surprised. I leave it on my nightstand charging overnight and check stats in the morning: sleep stages, blood oxygen, even snoring. More than enough to understand why some days I woke up exhausted. Four stars because the screen could be a bit better in direct sunlight, but indoors and at night it's perfect.