Amazon just listed the Apple Watch Series 3 for $169 – on sale. This is a great starter watch for anyone interested in dipping their toe in the waters with Apple’s tech. (They will need an iPhone to use it, though.) Series 3 runs smoothly with watchOS 6, and will be supported by the upcoming watchOS 7. (which includes sleep tracking)
These watches actually come with blood oxygen detection built in, but it isn’t enabled yet due to FDA restrictions. Once the FDA eases their rules, this will be great for early detection of COVID-19-like symptoms.