Yono, $150

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By wearing the Yono in your ear like an earbud headphone, Yono Labs claims that you can accurately track your fertility cycles and monitor your hormones. The Yono tracks your basal body temperature, notifying you of when you're at your most fertile period in your cycle. Tracking your temperature can be more accurate than tracking ovulation.

First published December 22, 2015: 2:55 PM ET