Recs.
Updated
Microsoft Band 2 is a fitness tracker with an impressive 11 different sensors in it.
Specs
Pros
Pro Natural feeling display
The display is slightly curved, making it more natural to wear and use. You also won't be hitting it off walls and doors as often as other watches because it doesn't stick out as far from your wrist as other fitness trackers.
The OLED display doesn't light up black pixels, meaning the background blends in perfectly with the bezels making for a more pleasing look as well as saving battery life when displaying mostly black colors.
Pro Smartphone connected
The Microsoft Band 2 connects to your Android, Windows Phone, or iPhone to provide notifications on your wrist. Swiping left from the main screen shows notifications that have been synced from the watch. It doesn't show context for these notifications however - just the number of missed notifications and their respective icons.
Cons
Con Band 2 is discontinued - no Band 3 on the horizon
Most likely due to the very high incidence of returns (due to charging issues and the straps cracking in half), the Band fitness tracker brand seems to be entirely discontinued.
Con Poor HR sensor + Poor data visualization
The fitness tracker's HR sensor is very inaccurate during HIIT/weight lifting movements, it takes forever to even lock-on, and once locked-on it doesn't stay locked-on. All of this contributes to very poor HR accuracy. To top it off, the app/web site does not display high-frequency data, it will plot a single HR point for every 1 minute of activity which makes it very, very useless.