garmin vivosmart 4 vs cms50f

Shnorky · Post by **Shnorky** » Fri Apr 17, 2020 5:04 am

Hi everyone

Just wanted to post a headsup. Last year I bought a garmin vivosmart 4, thinking it might help me track the oxygen levels during my sleep, as it's quite easy to wear and the battery keeps for a while.
Well it was showing O2 levels down to 81%-84% almost every night, scaring me quite a bit.
Until I bought a CMS50F, and compared the data, and everything was just fine.
So for anyone else with a vivosmart 4, please be careful, the data is not accurate. At most within 10-15% accuracy. Guess measuring at the wrist is not ideal.