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Echoing the other comment, I loved my Pebble because it was a smartwatch that was a watch first and foremost and everything after that was added to make life easier (rather than to pile on selling points that someone might want but that nobody needs). For example, the thing had a week long battery life (irrc the first gen iWatch had something like less than a day), but even when it hit the bottom 10% of the tank, it turned off non-essentials (like Bluetooth, calendar, customizations, etc) and just kept going on a default watchface. The UI was simple, easy to navigate, and generally useful. Physical buttons meant that I never had to fight with a touchscreen to clear notifications or check my calendar.

Plus the whole thing was stupid customizable. On the software side, the community grew a fairly sizable market for watchfaces to show pretty much whatever suited your fancy (TimeStyle was always one of my favorites, but I was also fond of this Pokemon one). On the hardware side, the watch used a standard 20mm band so you could go as far as to match it to your outfit if you wanted (I had a nice metal band to go with my Steel so I could dress it up for college career fairs (and have my calendar send me a reminder when it was time to duck off to class)).