The Suunto 7 is the only Wear OS watch to use the Snapdragon Wear 3100's power saving sports mode. That's why it's able to last two days on a charge.
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The Suunto 7 has a trick to make battery life last so long: Its all in the SoC Read more Technology News Here -->
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SUUNTO 7 GPS Sports Smart Watch, Black Lime : Electronics
Suunto 7 Smart Watch