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"Best" is relative.

To me, the MetaWatch is the best, because it does exactly what I need it to without being a distraction and it has great battery life. Others will feel it's limited to the point where it's totally unnecessary and instead want an iWatch.

So take a few minutes, think about what you need and what you want, write down pros and cons of all watches available to you, then simply choose the one that's best for you.
 
Depends if you want just notifications on your wrist, an extension of your existing smartphone, or if you want a full blown phone replacement on your wrist like the Neptune Pine or Omate. Personally I think the watches like the pebble and Gear are useless and duplicate functionality that might take a millisecond more, ie; glancing at your phone.
 
The one with the most development is the Pebble. Don't know if it makes it the best.

As of now Pebble is doing great in field of SmartWatches. But in coming time there will be more SmartWatches... Possibly one from Apple Itself.
 
Having used a few, I still think Pebble is the best. Especially if you use an Android phone. There is a million tweaks available for it to really make it do what you want it to do.
 
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