I've bought several fitness trackers for my wife over the years and they inevitably end up in my desk drawer until I sell them on eBay. Most recently, my wife wore a 40mm Apple Watch. She still found it too big for her wrist and wanted the battery to last more than a day. I have a Garmin Venu watch that I really like. When Lily's watch came out, I bought it for her for Valentine's Day. It works almost as well as my Venu. Garmin has managed to pack a lot into a small package, including a 5-day battery life, likely thanks to the use of a monochrome screen. Their only complaint is that we haven't figured out how to disable ALL notifications from their iPhone. I'm sure we're missing something obvious. (I use my Venu with Android and it has many more options.) I/she recommends this tracker if you need accurate fitness and sleep tracking in a small package.
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