A sports reporter says she learned her boyfriend was cheating on her after noticing a spike in activity on his Fitbit.

Jane Slater, 38, a correspondent with the NFL Network, tweeted "an ex-boyfriend once got me a Fitbit for Christmas. I loved it. We synched up, motivated each other... Didn't hate it until he was unaccounted for at 4am and his physical activity levels were spiking on the app."

An Ex Boyfriend once got me a Fitbit for Christmas. I loved it. We synched up, motivated each other... didn’t hate it until he was unaccounted for at 4am and his physical activity levels were spiking on the app 🥴wish the story wasn’t real. https://t.co/npRkLJYYz0 — Jane Slater (@SlaterNFL) December 5, 2019

"Spoiler alert: he was not enrolled in an OrangeTheory class at 4am," she continued

Fitness apps can track just about everything you do, says tech expert Reid Blackman.

“If you are trying to be private, you should not wear one,” he told Inside Edition. “Every device now is connected to the internet."

Slater says she was heartbroken when she discovered seven years ago that her boyfriend was cheating, but "it's a story my friends and I laugh about now."

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