Here is the one thing to understand before buying any of them: Oura Ring 5, Samsung Galaxy Ring and Whoop do not measure sleep stages directly. They estimate them. They see your pulse, small changes between beats, movement, temperature and sometimes blood oxygen. Then software guesses whether you were awake, in light sleep, deep sleep […]

I want to be very clear from the start: I am not a professional athlete. I am not training for the Olympics, and I don’t have a sponsorship deal with any fitness tech company. I am Alex Warenstein, a 47-year-old man who spent a year hell-bent on fixing his chronic insomnia and sleep maintenance issues. […]

If you have read my story, you know that I have spent the better part of the last few years waging a war against insomnia. I have strapped almost every sensor imaginable to my body—from the Wellue O2Ring on my thumb to the Apple Watch on my wrist, and even EEG headbands on my forehead. […]

The smart ring market has exploded. What was once a niche gadget for Silicon Valley biohackers is now a mainstream accessory. But heavy is the head that wears the crown. For years, Oura was the only serious player. Now, in late 2025, they face the Samsung Galaxy Ring on the Android side and a software-empowered […]

Apple Watch sleep tracking has matured into something genuinely useful—especially on the newest hardware, Apple Watch Series 11 and Apple Watch Ultra 3. But “useful” and “precise” are not the same thing. If you’re here because you want to know whether Apple Watch sleep stages are accurate—and whether that deep sleep data matches how you […]